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Vegan Diet in Sports and Exercise – Health Benefits and Advantages to Athletes and Physically Active People: A Narrative Review

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Wirnitzer. Int J Sports Exerc Med 2020, 6:165
Volume 6 | Issue 3
DOI: 10.23937/2469-5718/1510165
International Journal of
Sports and Exercise Medicine
• Page 1 of 32 •
Open Access
ISSN: 2469-5718
Wirnitzer. Int J Sports Exerc Med 2020, 6:165
Citaon: Wirnitzer KC (2020) Vegan Diet in Sports and Exercise Health Benets and Advantag-
es to Athletes and Physically Acve People: A Narrave Review. Int J Sports Exerc Med 6:165. doi.
org/10.23937/2469-5718/1510165
Accepted: May 13, 2020; Published: May 15, 2020
Copyright: © 2020 Wirnitzer KC. This is an open-access arcle distributed under the terms of the
Creave Commons Aribuon License, which permits unrestricted use, distribuon, and reproducon
in any medium, provided the original author and source are credited.
Vegan Diet in Sports and Exercise Health Benets and Advantag-
es to Athletes and Physically Acve People: A Narrave Review
Katharina C Wirnitzer1,2,3,4*
1Department of Subject Didaccs and Educaonal Research and Development, University College of
Teacher Educaon Tyrol, Austria
2Department of Sport Science, Leopold-Franzens University of Innsbruck, Austria
3Research Centre Medical Humanies, University of Innsbruck, Austria
4Life and Health Science Cluster Tyrol, Subcluster Health/Medicine/Psychology, Tyrolean University
Conference, Austria
a fullled life, and is also recognized as a fundamental
social value [1] (p. 125). Moreover, it is the major pre-
requisite for a good tness level and sporng success
[2] (p. 401). The close connecon between health and
the lifestyle factors of nutrion and sport and exercise
is considered to be undisputed. However, since food
and sports are both considered ‘medicine’ [3-5] (p. 23),
[6] (pp. 9-14, 38, 100) their connuous inter-related ap-
plicaon is a highly eecve but simple tool for improv-
ing individual health, especially for athletes. Moreover,
because personal behavior (eg. food choices) has the
greatest potenal to harm or heal (40 %) [7] the athlete
has the most impact on one´s state of health, whether
for good or ill [2,7,8] (p. 409).
The concept of vegetarian or vegan diets had been
rmly linked to sports and exercise even in ancient his-
tory [2] (pp. 409, 420, 423). However, since 2017 there
has been a higher frequency of publicaon of review ar-
cles on veganism in sports than ever before, which all
contribute to and reect the increasingly high scienc
interest in the linkages between a vegan diet and sport
and exercise.
Within a meframe of 16 years, between 2004 and
2020, nine review arcles considering plant-based diets
in relaon to sports have been released [9-18], with ve
addionally focused on vegetarian diets or to a lesser
REVIEW ARTICLE
Check for
updates
Abstract
Health is one factor in leading a fullled life. Since food and
sport are considered to be ‘medicines’, their continuous in-
ter-related application is a highly effective but simple tool
for improving individual health. However, being a healthy
human is a prerequisite for becoming a successful athlete.
Vegan diets are booming in the mainstream and in sport.
From current sporting success all the way back to ancient
times, it is evident that vegans can win races up to profes-
sional levels and even break records. However, despite the
sound health benets of vegan diets, vegan athletes are
frequently faced with prejudice on unsubstantiated grounds.
Therefore, this review considers the various advantages of
the vegan diet for young and competitive athletes. It en-
compasses early studies and compares the potential ben-
ets and risks by looking at the quality of animal and plant
protein. The knowledge that vegan diets are compatible
with sports performance has the potential to encourage ath-
letes and their families, coaches, and experts in health and
sports to be more open-minded when an athlete expresses
his/her desire to adopt a vegan diet. A short outline of the
future perspectives of research needed is given.
Keywords
Sport, Physical exercise, Physical education, Vegan, Vege-
tarian, Plant-based, Health
*Corresponding author: Katharina C Wirnitzer, Department of Subject Didaccs and Educaonal Research and
Development, University College of Teacher Educaon Tyrol, Austria
Introducon
Health is a prerequisite for and one factor in leading
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Wirnitzer. Int J Sports Exerc Med 2020, 6:165 • Page 2 of 32 •
plant-based diets in the public and in sports around the
globe while being much debated among sport sciensts
and sports nutrion experts at the same me.
On a global basis, the numbers of vegetarians and
vegans have been growing at even faster rates than had
once been ancipated [26,31,32]. 6% of the US popula-
ons are vegetarian (4.3 million) and vegan (3.7 million)
[33]. About 10% of Europeans (75 million) adhere to
some kind of vegetarian diet [34], with 10% of the Aus-
trian (880,000), German (8.7 million), and Italian (1.2
million) populaons [35-37], 13% of the Brish [38] and
14% of the Swiss populaon (1.2 million) [39] now iden-
fying themselves as vegetarian or vegan. Moreover, the
vegetarian and vegan lifestyles are relevant especially
for the peer-groups of younger generaons, with the
so-called “millenials” (or “Generaon Y”, young adults:
22-38 years) as key of the current movement in the pub-
lic and main drivers for the global avoidance of meat
and increased trend towards plant-based diets [29,30]:
25% of 25-34 yr-aged in USA refer to themselves as veg-
etarian or vegan [29]; 25% of the 18 yr-aged in the UK
eat vegetarian or vegan [40,41] while 30% of 18-24 yr-
aged Brits have already considered to eat vegan or are
already vegan [42]. Furthermore, 44% of Generaon Z
(young people < 24) rate the vegetarian and vegan life-
styles as cooler than smoking [43], 1 out of 12 parents
in the UK (8.3% of 2.200) raise their children (0-12 yrs.)
vegan due to health benets as the main reason (61%)
[44], and increasing numbers of the Baby Boomers gen-
eraon at the age of 55+ yrs in the USA are going vegan
mainly due to health [45].
Based on the background numbers of 10-44% vege-
tarians and 1-17% vegans [33,38,42,43,46], there would
be 2-8 vegetarians and 1-4 vegans in any group of about
20 people (eg. a class of pupils or students, employees
in a company or department, and even team-mates in
a sports team). As a consequence, it is very likely that
there is no longer any social group or sports team with-
out a vegan person or athlete. Unpublished data from
our laboratory considering the NURMI Study (Step 1)
shows the prevalence of 35% vegans (n = 1.029), 21%
vegetarians (n = 615) and 44% omnivores (44%, n =
1.315) starng in running events.
There are some professional vegan athletes who are
acve in endurance disciplines, such as Fiona Oakes (ul-
tra-marathon running, set her fourth world record in
2018); Sco Jurek (ultra-marathon running, has set mul-
ple records including the speed record for compleng
the Appalachian Trail of approximately 2,200 miles in 46
days, 8 hours, 7 minutes in 2015); Rich Roll (ve-me Ul-
tra Ironman triathlete); or Gerlinde Kaltenbrunner (the
most successful female mountaineer in the world, has
climbed all 14 eight-thousanders without supplementa-
ry oxygen or the help of porters). While Novak Djokovic
(Number 1 in the 2018 ATP ranking list, 14-mes Grand
Slam winner, eg. Wimbledon, Australian Open) and Ser-
extent on vegan diets [11,13,14,16-18], summarizing the
lile informaon available. These reviews were mainly
based on studies performed on vegetarian non-acve
populaons or athletes, with ve focusing on nutrional
consideraons [9-11,13,14], and ve addressing sports
performance [12,15,16,18]. However, except for Fuhr-
man and Ferreri [11] who were the rst to share their
experiences of working with vegan athletes, none of the
authors have published original research considering
veganism and sport or have shown evidence of knowl-
edge or experience of supervising vegan athletes. In ad-
dion, no review has addressed the most basic prereq-
uisite for athlec (peak) performance, which is health
above all. Addionally, data on veganism connected to
sports and health has been published from our labora-
tory [2,19-25].
Therefore, the goal of this review is to consider the
various health benets resulng from a vegan diet to
athletes and the concept that it might provide advan-
tages for (young, compeve) athletes. In presenng
relevant informaon for both experts and praconers
in the eld of sports and physical educaon, the author
has two decades of experience working with athletes of
all performance levels and advising them how to switch
to and to maintain a healthy, needs-based vegan diet.
To the best of the author´s knowledge, this review is the
rst to provide a special perspecve which cuts across
the three disciplines of diet, sports and health. This re-
view is also the rst to combine scienc raonale from
evidence-based data with relevant anecdotal informa-
on in order to support a more healthy approach to
sports nutrion counseling of athletes. Based on this sol-
id foundaon, the intenon is to nudge experts, ranging
from sports praconers such as coaches, dieans and
families to specialized sciensts in the elds of sports,
nutrion, medicine and health, to be more open-mind-
ed and not to reject out of hand an athlete’s expressed
desire to switch to a healthier dietary paern, including
a vegan diet.
Background
Nowadays, giving up meat and animal products is a
steadily growing trend, mainly in industrialized naons,
with the vegan diet (no foods from animals sources) be-
ing part of the vegan lifestyle (no products from animal
origin at all) [26,27] (pp. 7, 12). Vegan diets not only
constute a current boom with increasing acceptance
and appreciaon amongst the public [28-30], but the
numbers of vegetarians and vegans are also increasing
in sports, including several famous athletes at world
class level. Therefore, it is likely that the number of veg-
an athletes is rising across all tness levels in school,
recreaonal, amateur and professional sports.
The book Thrive: The Vegan Nutrion Guide to Op-
mal Performance in Sports and Life and the documenta-
ry The Game Changers are not only tles of well known
bestsellers, but also reect a current movement towards
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(1) Performances of vegetarian or vegan athletes
were found to be two-fold to three-fold higher in
terms of endurance, stamina and strength.
(2) Time needed for complete recovery was found
to be markedly reduced in strict vegetarians,
with some cases needing a h of the me that
meat-eang athletes needed [49,53].
In the 1980s, over a seven-year period of eld studies
(1983-1990) consisng of several series of super-mara-
thons, trekking tours at high altudes, and desert tra-
verses on foot [55] (pp. 18-20, 51-52, 60, 63-65, 159-
174), [56] (pp.19-20), the potenal that emerges from
following strict vegetarian (vegan) diets was demon-
strated, as well as the posive eects on physical per-
formances resulng from Galina Schatalova’s specic
dietary concept for metabolic eciency (minimal uid
and energy supply [55] (pp. 16, 51, 60, 64-65), [57] (pp.
17-18) and with whole plant foods [55] (p. 200). The
endurance performance of the subjects of the experi-
mental groups was reported as being beer than those
in the omnivorous control groups for all eld trials [55]
(p.161). The vegetarian hikers were beer able to cope
with severe physical stress and to sustain physical bur-
dens, even at high altudes and under extreme condi-
ons [55] (pp. 164-172).
Together, these data indicate that strict vegetarians
(vegans) are able to tolerate and even sustain higher
physical burdens for longer duraons, and to recover
from physical stress more rapidly. This supports the as-
sumpon that vegetarian and vegan diets are compa-
ble with peak performance sports Table 1 [20].
Back in ancient mes, gladiators and philosophers
knew that strict vegetarian (vegan) diets are compa-
ble with physical and intellectual performances. Just to
name one representave, the Greek Pythagoras was
not only a prominent philosopher and mathemacian,
but an Olympic st-ghter, too [2,58], (p. 423). In order
to survive their ghts in the arena, the gladiators had
to be strong, skillful and persistent. Therefore, dietary
schemes of ghters were aimed at keeping them eec-
ve and t. The gladiators followed a specic diet (‘glad-
iatoriam saginam’ or even ‘hordearii’) that consisted of
large amounts of legumes, pulses, and grains (78% from
peas, lenls, barley, wheat, millet, corn), but explicitly
with lile or no meat. Based on archeological excava-
ons, the gladiator´s intake of protein from animal or-
igin has been demonstrated to be generally very small
[58,59]. According to Longo, et al. [58] the best ghters
in ancient mes were vegetarian.
Dang back to even earlier in human evoluon, di-
etary behavior and habits have been associated with
physical and cognive performance [2] (pp. 409-410).
Based on Neanderthal ecology from genomic data
showing regional dierences, it has been suggested that
human ancestors in prehistoric Spain (El Sidron cave)
ena Williams (Number 16 in the 2018 ATP World ranking
list, 23-mes Grand Slam winner, eg. Wimbledon, Aus-
tralian Open, French Open, US Open) are role models
for vegan tennis athletes, others are representaves of
technical sports, such as Meagan Duhamel (pairs gure
skang; double Olympic champion, Pyeong Chang 2018;
Olympic silver medal, Sochi 2014), power and strength
disciplines, such as Patrik Baboumian (three-me world
record holder at Beer Barrel Li; Front Hold 20 kg; Yoke-
walk 555.2 kg over 10 m in 2013, topped to 560 kg in
2015); Patrick Reiser (world champion Natural Body-
building); Kendrick Farris (Olympic Weight Lier, Rio
2016; set the American record in the 94 kg weight class);
or Frank Medrano (Superhuman Bodyweight Workout
dominaon), and even in Formula 1, such as Lewis
Hamilton (won the Formula 1 World Championship in
2019 for the sixth me). Even in team sports such as
ice hockey, basketball and soccer (Forest Green Rovers,
UK, were the rst vegan football club), more and more
athletes are following vegan diets, too. In addion, in
2014 in Brazil the German Naonal Football Team won
the World Championship while temporarily adopng a
vegan diet.
These and numerous other successful athletes who
adhere to vegan diets provide sucient evidence that
for all kinds of sports, ranging from high-level endurance
and ultra-endurance to power and strength disciplines,
athlec success (victories, world records, etc.) can be
achieved when following a vegan diet. Therefore, it is
reasonable to conclude that a vegan diet is compable
with peak performance in elite and professional sports.
Early studies on strict vegetarians and plant-based
ancestors
The link between sports and exercise and a strict veg-
etarian (vegan) diet has been an area that has aracted
scienc interest for more than 150 years (an overview
is presented in Table 1) and is at present of growing im-
portance. It can even be traced back to ancient mes or
early pre-history [2] (pp. 409, 420, 423).
The inial scienc interest in vegetarian diets as
they relate to athlec performance emerged at the end
of the 19th century [47,48], and at the beginning of the
20th century, resulted in the rst studies conducted in
this eld. Dierent sciensts invesgated if and how
vegetarian diets inuence physical performance by con-
ducng research at Belgium [49], Yale University Medi-
cal School [50-52], and Academie de Medicine de Paris
[53], almost at the same me. Independent of each oth-
er, they found posive eects on exercise performance.
These inial data comparing strict vegetarian athletes to
meat-centered athletes (me to exhauson: On a sta-
onary bicycle, liing an external load by handgrip me-
ter, holding horizontal arm posion, deep knee bends)
can be summarized as containing two major ndings
[49-54]:
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Setting Timeline Studies & Results (in extracts, abbreviated)
Laboratory testing
1904-1907
1904 & 1907: Plant-based diets affecting physical performance (hand-grip meter, stationary bicycle)
[50,51]
¾Male subjects (students, fellow faculty members, and himself)
¾Plant-based diet: Subjects exercised more, with less fatigue, vs. diet based on animal protein
1907: Series of tests (holding horizontal arm position, deep knee bends) comparing stamina and strength
of meat eaters vs. vegetarians (Fisher’s classic study) [52]
¾Males, fed different diets, consecutively tested: Meat-eating athletes, vegetarian athletes,
vegetarian sedentary subjects
¾Compared to meat-eaters: Vegetarian athletes had twice the stamina, far more endurance
¾Meat eating athletes: Outperformed even by vegetarian sedentary subjects
¾Difference in endurance performance was entirely put down to diet
¾Strong evidence: Vegetarian diets increase endurance
1968
Fisher’s classic study repeated (stationary bicycle to measure strength and endurance) [54]:
¾Initially mixed diet (meat, vegetables) -> pedalling time until muscle failure: 114 min
¾Re-test: High animal protein diet (rich in meat, milk, eggs) -> big drop in time: 57 min
¾Final re-test: Strict vegetarian (vegan) diet (grains, vegetables, fruits; no animal foods) ->
pedalling time: 167 min
¾Vegan diet had:
Three-times better performance than animal protein-centered
One-third better performance than mixed diet
1986-1992
2 laboratory studies [280,281] considering the physical performance of vegetarians, both comparing
tness of vegetarian to non-vegetarian athletes
¾No differences in exercise performance
Field studies
1983-1990
Schatalova’s ‘Concept of Curative Healing’, ‘System of Natural Healing’ [55] (pp. 18-20, 51-52, 60, 63-
65, 159-174), [56] (pp. 19-20):
1983 - 1984:
¾Series of 4 super-marathon races (500 km, 4-7 stages, 50-72 km/day, speed: 14-18 km/h)
¾Series of mountain trekking tours
Altitude of about 5,000 m (25 km/day)
High altitude camp at 3,000 m altitude
Foot march crossing 4 mountain passes over 23 days
1987-1990:
¾Series of 4 expeditions of desert traverse on foot crossing Central Asian deserts (250-500
km, 30-35 km/day)
1989
Deutschlandlauf 1987 [282-286]: Inuence of a 1,000-km ultra-run on lipid metabolism, Western diet (n
= 30) vs. wholesome vegetarian diet (n = 25)
¾Runtime of vegetarians (114 h 14 min) was approximately 2 hours faster than that of
omnivores (116 h 29 min)
¾Use of medications and drugs, and need of medical supply, was less in vegetarians vs.
controls/other ultra-runners
1997
National Runners’ Health Study (national US survey) [287]: Interactive effects of running (weekly
mileage) and diet (weekly intakes of red meat, sh, fruit and alcohol), by self-reported food intakes of
289 vegetarians and 62 vegans, vs. physician-supplied medical data (8,891 omnivores)
¾Compared to omnivores, vegetarians ran signicantly further, had higher BMI, higher fruit
intake, less alcohol
¾Dietary assessment was limited -> lack of data on other foods/specic nutrients prevented
any conclusion that red meat or fruit caused the associations
Table 1: Overview of early studies on strict vegetarian (vegan) diets in sports.
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ambious endurance athletes are at signicant risk from
atherosclerosis. Higher exercise-induced energy needs
are usually covered by higher intakes of animal foods
from a mixed diet, but the high intakes of saturated fats
and cholesterol along with the lack of health-promong
items (eg. ber, anoxidants) may contribute to arterial
changes that promote atherosclerosis [16]. This might
explain why endurance athletes more oen develop
severe atherosclerosis than non-acve people (high-
er values for coronary plaque: 44% vs. 22% total [68],
and (non-)calcied plaque [69,70]. Moreover, the carot-
id artery inma-media thickness has been found to be
signicantly higher in control groups following a typical
non-vegetarian diet (0.74 mm) and even in endurance
runners (0.63 mm), than in vegans (0.56 mm) [71,72].
Atherosclerosis can severely narrow not only the coro-
nary arteries of soldiers and athletes by the age of about
20 years (75-90%) [69,73], but also the arteries of the
brain and peripheral arteries of the upper and lower ex-
tremies, which consequently negavely aects athlec
performance [16].
In this context, there is enormous potenal to make
an important contribuon to the abandonment of the
1-dimensional perspecve of health, whereby either
one of these lifestyle factors is usually viewed and im-
plemented in isolaon, namely: either nutrion or sport
and exercise [2] (pp. 418-419).
Dual guidelines on supporng good health have in-
extricably linked diet with sports and exercise recom-
mendaons since 2002. The goal has not only been to
avoid unnecessary body fat accreon on a long-term ba-
sis through a balanced energy turnover, but also to pro-
mote and improve lifelong health and well-being, aim-
ing to complement diet with acvity guidelines compa-
ble with reducing risk factors in order to prevent chronic
diseases [2] (pp. 418-419). Diet and physical exercise
are actually good predictors of mortality compared to
other risk factors for premature death, such as the ve
highest-ranked risk factors worldwide: Hypertension,
tobacco use, high blood glucose, physical inacvity, and
overweight/obesity contribute to 13%, 9%, 6%, 6%, and
5% of global deaths, respecvely [65,66,74-78]. Based
on science-based recommendaons, the world´s lead-
ing nutrional, sports and health organizaons have
released guidelines which emphasize the importance of
permanently balancing diet with sport and exercise in
order to achieve beer individual health [2] (pp. 418-
419).
Therefore, in order to achieve beer health for ath-
letes, the foundaon of health should be based on a
minimum of two strategies which are ideally interwoven
and implemented on a regular basis in every day sched-
ules, with the two main elements being (1) A healthy
diet permanently linked to (2) Regular sport and exer-
cise. A healthy diet – at best whole food vegan diets
intrinsically linked to regular sport and exercise – at best
were vegetarians. Their meatless diet was characterized
by mushrooms, pine nuts and moss [60]. In contrast,
the Belgium Neanderthals (Spy cave) followed a heavily
meat-centered diet [61,62].
Together, this shows that a meatless approach to
physical performance is not new but rather is ancient
knowledge that is currently being increasingly taken
into account.
Sport alone is not enough to aid health and exer-
cise performance
In sports, the goal has always been to excel over oth-
ers and to outperform opponents, which is clearly rep-
resented by the saying ‘higher, faster, further’.
Aer more than 50 years of epidemiological studies,
it is accepted that cardiorespiratory tness, which re-
sults from both healthy acvity paerns and increased
levels of sports and exercise, leads to beer health [63].
A current study supports this by examining the eects of
lifelong involvement in aerobic exercise (on average 52
years, exercising 7 h/week on 5 days/week) on cardio-
vascular and skeletal muscle health in 75-year-old sub-
jects. The data show that substanal benets emerge
from a lifelong adherence to aerobic exercise. In addi-
on to aerobic capacies 40% higher than their inac-
ve age-matched peers, the acve old subjects were
calculated to have the cardiovascular health of people
30 years younger than themselves when compared to
established data of capacies rated to be the norm [64].
It is generally accepted that sport and exercise are
powerful tools that posively aect health and thus aid
the prevenon of severe illnesses [65]. Regular sport
and exercise, at best on a daily basis, has been shown
to be prevenve in the development of chronic diseas-
es, for example reducing the risk of coronary heart dis-
ease, stroke, diabetes, hypertension, and some cancers.
Moreover, sport and exercise are key to balancing ener-
gy supply and ulizaon, and thus for controlling Body
Weight (BW) [66].
However, physical acvity, sport and exercise as a
single mechanism for promong individual health and
aiding a healthy lifestyle are not enough, even when
pracced outdoors. If that were true, farmers, garden-
ers, soldiers and others who have physically demanding
jobs, which are to some extent outdoors (eg. profes-
sional athletes), would not get severely ill or suer from
(chronic) diseases. The following example exemplies
the fact that a 1-dimensional approach to health, espe-
cially for athletes, is limited.
The founder of the jogging movement, James Fuller
Fixx, was convinced that non-smoking and sport were
enough to ensure health and longevity, but that healthy
eang was not important. However, he died from a heart
aack during his daily jogging roune [67] (pp. 407-408).
A current study has found that even well-trained and
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health benets increase as the amount of food from an-
imal sources decreases, and concluded that the vegan
diet is the healthiest diet overall, even healthier than
vegetarian diets [94]. The health status of vegans is
more oen within the normal range (eg. blood pressure,
cholesterol levels, and BW) [83] (p. 92), [85] (pp. 105-
106). The BW and Body Mass Index (BMI) of vegans are
lower (adherence of ≥ 5 years) than vegetarians and om-
nivores [26,87,90,95-99], and vegans suer much less
frequently from being overweight and obese, and from
several other diseases [26,88,99]. Moreover, vegans are
more health-conscious (acve on a regular basis, no or
less consumpon of alcohol or tobacco) [85] (pp. 105-
106). Together, these aspects create the opmal basis
for improving an athlete`s performance.
The AND has declared in their current posion state-
ment [88] that well-planned vegetarian and vegan di-
ets are (1) Healthy, (2) Nutrionally adequate, match
dietary guidelines and meet current recommended in-
takes, (3) Provide health benets for the prevenon and
treatment of certain diseases, and (4) Are appropriate
for people at all ages as well as athletes. Seven of the
largest specialist associaons for nutrion worldwide
agree with the latest AND posions [100-107]. Howev-
er, there is a consensus that vegans have to take spe-
cial care to ensure a sucient supply of vitamin B12 by
reliable sources, such as fored foods or supplements
[26,88], [27] (pp. 48,102), [85] (p. 121).
Regarding the prevenon of diseases, the AND [26]
posion not only conrms, but also underlines and
explicitly highlights their former statement [85], that
“there are tremendous advantages toward prevenon
of chronic health condions by adhering to a vegetarian
eang paern”. The evidence-based literature proves
that vegan diets posively inuence the development,
prevenon, and therapy of chronic, inammatory, and
degenerave diseases. Regarding prevenve and ther-
apeuc diets, the vegan diet is highlighted as being
the most benecial diet [26,88] known to serve as an
eecve therapeuc tool in relaon to hypertension
[87,108-111], diabetes mellitus type 2 [26,108,112-116],
atherosclerosis [26,31,88,95,117-119], and Cardiovas-
cular Disease (CVD) [93,108-111,115,118-127], amongst
others [84] (p. 92), [85] (p. 123). Moreover, with special
relevance to athletes, the vegan diet in parcular ben-
ecially aects both BW control (overweight, obesity)
[26,90,93,95-99,108,115,127-129], microinammaon
[17,130], and chronic systemic inammaon [99].
Overall, the health benets of vegan diets are sound,
in addion to the good health of vegetarians and vegans
being sound, too [90,131-133]. Thus, veganism can be
conclusively recommended [26,27,134], (pp. 105-106,
196-198), [85] (p. 123), even for athletes, as the basis
for maximum health, which itself is a prerequisite to
sporng performance and success, ranging from daily
parcipaon to winning medals Table 2.
moderate intensity on a daily basis – may oer the most
promising key intervenon for both an athlete`s sustain-
ably opmum health and the resultant physical perfor-
mance [2] (p. 391), and thus should be transferred and
integrated into the athlete’s daily schedule.
As both these crucial elements of health occur nat-
urally mulple mes in a day, a healthy vegan diet can
be easily and praccally applied to sports and various
sengs, if desired.
Vegan Diet - Foundaon for an Athlete’s Health
and Sporng Success
There is a consensus that diet, in addion to but
more important than sport and exercise, is the basic
foundaon for health, and thus is highly relevant to an
athlete`s state of health. Therefore, rather than focusing
on single foods or nutrients to address health problems,
holisc dietary schemes and comprehensive lifestyles
should be addressed [55-57,79-82], [55] (pp. 36-37, 62-
65, 133-138), [83] (p. 38), [84] (pp. 36-37).
Nutrion should supply the body with all vital nutri-
ents, preserve performance capacity (physical and men-
tal), reduce the risk of chronic diseases, and promote
health [85] (pp. 49-50). However, modern nutrional
behaviors are known to cause dietary-induced chronic
diseases and premature death [2] (pp. 387-388). A grow-
ing body of evidence-based data underlines the fact that
diet, along with other lifestyle factors such as sport and
exercise, plays a key role in the development of certain
diseases [2] (p. 413).
Based on scienc evidence, there is a growing in-
terest in and appreciaon of vegetarianism [83,86], but
especially of veganism [27,85,87], [85] (pp. 49-50, 123).
Over and above energy intake, it is due to the charac-
teriscs of plant foods that there is a wide range of di-
et-related health benets from adopng vegetarian but
in parcular vegan diets [26,87,88]. Table 2 presents an
overview of the health benets resulng from vegan
(vegetarian) diets (without claiming to be complete).
Adequacy of vegan diets - benets to human health
The rst study ever performed on vegans which in-
vesgated their state of health, morbidity and mortal-
ity linked to chronic diseases was published in 1978
and showed disnct advantages of vegan diets over
non-vegan diets [89]. Two years later, in 1980, the Acad-
emy of Nutrion and Dietecs (AND, formerly American
Dietec Associaon: ADA) published its rst posion
statement on vegetarian diets. Since then, cumulave
evidence has repeatedly conrmed that vegetarians on
average are healthier than non-vegetarians.
Numerous reputable studies (e.g. Advenst Health
Studies 1 and 2, GEICO Study) support the clear bene-
ts of vegan diets compared to non-vegan diets [90-93].
Based on the scienc literature available, the Physi-
cians Commiee for Responsible Medicine found that
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Table 2: Overview of the health benets resulting from vegan diets.
No. Health benets (abbreviated) & important results (in extracts, abbreviated) References
1
Higher life expectancy and lifespan: Eating vegetarian for > 17 years has been
connected to + 3.6 years, particularly vegans have been reported to have the highest
life expectancy
Reduced mortality risk and lower risk of most main causes of mortality
Lower all-cause mortality (up to - 20%, maximum with fresh fruit - 21%)
Lower mortality from CVD
[89, 90, 92, 96, 133, 149, 164,
288-307], [83]
(pp. 92, 189)
2 Resting heart rate (associated with longevity, distinct gain in lifespan) in order to
protect, maintain and improve heart health and cardiovascular health [179, 181, 182]
3
Plant protein is adequate to meet protein requirements at all ages (balanced vegan
diet, when energy intake is adequate)
Total and daily protein intake is adequate (intake: 10-12% in vegans)
Current protein recommendations and also protein needs are met or exceeded
without the use of additional protein supplements
[9, 19, 20, 22, 26, 88, 170,
174-176], [163]
(pp. 15, 67, 77-79)
4
↑ Better up to highest rated diet compared to mixed diets considering quality of diet
contribution to healthy eating (Alternative Healthy Eating Index, Healthy Eating Index
2010 and the Mediterranean Diet Score)
/ Good/high quality of plant protein (grains, legumes, pulses, beans)
Plant protein provides all amino acids
Plant protein benecial to (sustainable) health
↑ Plant protein healthier than animal protein: Supplies almost no saturated fatty acids,
no trans-fatty acids, no dietary cholesterol, good source of complex carbohydrates,
ber, iron, zinc, resistant starch, antioxidants, phytochemicals
↓ Plant protein associated with
/ Good health of gastro-intestinal tract and heart
/ Good bone health (mineral density, no higher risk for osteoporosis and fractures)
/ Good muscle health (preserving muscle mass and strength, metabolic health,
functional capacity)
↓ Lower blood pressure
↓ Reduced blood lipid and LDL levels
↑ Improved insulin sensitivity
↑ Improved menopausal symptoms and female osteoporosis
↓ Reduced risk, lower incidences of certain cancers, and prevention (reversal) of
cancer
↓ Lower mortality risk and lower mortality from (1) CVD (- 12%) and (2) all-cause
(- 10%), a calculated reduction of up to - 10% in global deaths with 8.1 million
lives could be saved per year
[26, 31, 88, 146, 149, 162,
172, 175, 177, 178, 188, 243,
249, 308-318], [2] (pp. 388-
389, 402, 410-413, 416), [27]
(p. 43),
[163] (pp. 65, 74, 77-79)
5 Fewer biological hazards, toxic substances and noxious residues of chemicals
(agricultures, life stock farming)
[155, 156, 165],
[154] (p. 103)
6
↑ Naturally provides high nutrient density, and high amounts of complex carbohydrates
Meets nutrient recommendations
↓ Less calorie-dense, lower total calorie intake, less saturated fat, cholesterol intake
(than non-vegan diets)
/↑ Naturally provides the highest alkalizing potential (low-PRAL: specic fruits/
vegetables down to - 23 mEq/day; vegan meal down to - 22.9 mEq/dish; vegan diet
down to - 39 mEq/day)
[26, 88, 138-142, 144-146,
188, 203-206]
7
Species-appropriate diet
Adequate diet for all ages (pregnancy to elderly), and for athletes
Recommended as diet for permanent adherence (wholesome, natural, vegan diet),
counted among alternative diets, with vegetables, fruits, whole grains (products),
potatoes, legumes, nuts and herbs as central food groups
[26, 88, 187], [2, 55],
(pp. 36-37, 62-65, 133-138),
[83] (p. 38)
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8/Inexpensive and safe intervention (dual, integrated guidelines: Vegan diet
permanently linked to daily moderate sports and exercise)
[319-321],
[2] (pp. 418-419)
9
Good state of health is sound
Health status more often within normal range
↓ Lower BW and lower BMI (vegans are leaner)
Better BW control/management
↓ Lower blood pressure
↓ Lower blood levels of total and LDL cholesterol (with lower risk of CVD)
Healthier than non-vegans
↓ Suffer markedly less frequently from illnesses, infections and chronic diseases
Increased antioxidant status (to prevent LDL oxidation; to reduce exercise induced
oxidative stress; plant polyphenols protective to cardiovascular system)
Improved (signicantly lower) biomarkers of inammation and immune defense
(serum CRP, brinogen, interleukin-6; total leukocyte levels; lymphocyte
responsiveness; natural killer cell functionality)
↓ Less micro inammation and reduced chronic systemic inammation
↓ Associated with fewer allergies than with vegetarian diets
Lower morbidity
[12, 18, 26, 31, 87-90, 92, 93,
95, 97-99, 108, 122, 123, 128-
133, 137, 164, 262, 263, 266,
287, 291, 299, 306, 322-324],
[83] (p. 92)
tension, chronic kidney disease, low muscle mass, renal
lithiasis, non-alcoholic fay liver), and is associated with
the development of chronic diseases [144,146].
It is accepted that foods from animal sources are
mostly highly processed products [120,147], which, in
addion to protein, contain other components such as
sodium, nitrates and nitrites that are suggested to nega-
vely aect health [148-153].
It is well-known that products from animal sources,
such as meat and processed meat, chicken, sh, shell-
sh and seafood, milk and dairy products, and eggs,
have been repeatedly detected to have markedly high-
er contaminaon by toxic substances than products
derived from plant foods. These substances include
residues from pharmaceucal drugs (e.g. hormones to
increase growth, ferlity and lactaon, ataraccs, tran-
quilizers and anbiocs), industrial toxins (e.g. dioxins)
and heavy metals (e.g. lead or mercury) [2] (p. 400), and
higher levels of pescides (eg. 14-fold for meat, 5-fold
milk) [154]. Up to 92% of human exposure to dioxins,
furans and Polychlorinated Biphenyl (PCB) comes from
the consumpon of animal foods (meat, sh and shell-
sh, and dairy products), compared to about 8% result-
ing from eang plant foods [155,156]. The exposure
to hazardous residues is detrimental to human health
[26,147], [2] (p. 400), and is parcularly detrimental to
an athlete`s state of health.
Evidence-based data has also shown frequent meat
(including sh and seafood) consumpon to be the ma-
jor risk factor for chronic disease [27] (pp. 105-107).
Disadvantages of red and processed meat consumpon
mostly result from the excessive intake of saturated
fats [157,158], along with other substances contained
in animal products, and result in an intensied risk of
Animal protein detrimental to overall state of
health: A typical ‘Western diet’, also described as a
balanced mixed diet (generally dened as the refer-
ence diet), is characterized by high intakes of calories,
total, trans and saturated fats, cholesterol, meat (espe-
cially red and processed meats) and animal products,
salt, sugar and rened carbohydrates, together high in
‘empty’ calories, but with low intakes of vegetables and
fruits, dietary ber, micronutrients, and phytonutrients
(eg. polyphenols, omega 3 polyunsaturated fay acids)
[135-137]. The Western diet is a known risk factor for
metabolism-induced inammaon associated with obe-
sity [137].
It is further characterized by a high dietary acid load
[138-145] that ranges of 50-70 mEq/day. Generally, a
specic kind of diet can markedly aect the metabolic
regulaon of the organism with its characterizing food
items, micronutrient prole, and capacity of acid or
base producon providing acid or alkaline precursors
inuences systemic blood acid-base status (pH-value)
and acid-base balance (eg. quaned by PRAL (mEq/100
g) - the potenal renal acid load) [144,146]. It is well
known that foods and dietary paerns rich in protein
(high-PRAL food items like eg. meat, cheese, eggs) in-
crease the acid producon and lead to high acid load
and systemic acidosis, while most plant foods have a
low potenal to produce acids (low-PRAL food items)
[138,139,141,144], even from plant-based dietary sup-
plements [140].
However, diet-induced low-grade metabolic acidosis
is buered mainly by increased bone resorpon, and
is associated with the development of metabolic alter-
aons and complicaons (eg. bone disorders negave-
ly correlated with bone mineral density, but posively
with fracture risk, insulin resistance, diabetes, hyper-
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fat content) [163,171], which aid BW management.
Plant sources of protein, such as nuts and legumes, also
provide numerous other nutrients benecial to health,
such as carbohydrates (up to 50%, low glycemic index),
dietary ber (up to 37%), vitamins, minerals and phyto-
chemicals [83,162].
According to the AND [26], vegetarian and vegan di-
ets provide the same protein quality as meat-based di-
ets. Research suggests that, although vegan diets may
be limited in leucine, lysine, threonine, tryptophan, or
methionine [31,172], the quality of plant protein such
as of grains and legumes is good, but the protein quality
of soy in parcular is comparable to animal protein [26],
[163] (pp. 74, 77, 79).
Based on a well-balanced vegan diet with adequate
total calorie intake, which includes a big variety of plant
foods and supplies sucient amounts of all essenal
amino acids [26,31,88,171,173-175], [163] (pp. 65,78-
79), vegans of all ages typically can not only be ade-
quately supplied with enough protein to meet their rec-
ommended daily intakes, but can even exceed their pro-
tein requirements [9,26,88,175], [163] (pp. 15,67,78),
without the use of addional protein supplements
[176]. According to ample scienc evidence, both the
amino acid and protein needs of non-acve vegans, and
even the higher requirements of athletes, are easily met
with a vegan diet [26,88,173,175,177], [163] (pp. 65,
78-79). Moreover, the AND [26] and ADA [31] together
with experts on protein nutrion agree that - when an
assortment of plant foods is eaten over the course of a
day there is no need for nutrional behavior like in-
tenonal ‘protein combining’ or ‘complemenng’ when
composing and preparing meals in order to obtain all
the essenal amino acids, not even for vegan athletes
[26,31,177].
The Framingham Third Generaon Study has recent-
ly found that dietary protein is associated with muscu-
loskeletal health, independent of dietary paern [178].
Therefore, a vegan diet can equally contribute to muscle
health just like any other dietary paern.
Moreover, it is generally accepted that heart health
and resng heart rate, and thus cardiovascular health,
are highly aected by both diet and sport and exercise.
However, the evidence-based literature shows diet to
be the most powerful lifestyle factor in relaon to health
protecon and a healthy heart, even more than physical
exercise [179], [2] (pp. 390-391).
In a 16-year follow-up study, an increased resng
heart rate has been found to result in premature death
more frequently [180]. In addion, an increased risk of
premature death (+ 10 – 20%) has been found to result
from every 10 bpm increase in heart rate, with a resng
heart rate of > 65 bpm having a strong independent ef-
fect on premature mortality [179]. Therefore, a drop in
resng heart rate from 70 to 60 bpm, following cardiac
slowing (myocardial metabolic rate associated with re-
hypertension [159], CVD and strokes [148], diabetes
mellitus [160], cancer [161], venous thromboembolism
[157], impaired bone health and osteoporosis, and re-
nal disease [162,163] (pp. 43, 66). Moreover, the asso-
ciaon of high intakes of animal protein with a reduced
lifespan [83] (p. 189), [149], by causing a higher risk of
premature mortality from (1) all-causes (+ 2 – 34%), (2)
CVD (+ 8 – 29%), and (3) cancer is generally accepted.
Furthermore, a recent study has found that even with a
high intake of fruit and vegetables (food groups known
to be protecve to health), the negave eects of red
meat consumpon on mortality (higher risk of all-causes
(+ 21%) and CVD (+ 29%)) were persistent and could not
be counteracted or compensated for [164].
Overall, the convenonal dietary paern is known to
cause severe health problems [136]. Therefore, despite
the claimed benets of diets based on meat and oth-
er animal protein, challenges to human health remain
[165].
In the light of evidence based on large-scale prospec-
ve cohorts, epidemiological studies [2] (pp. 412-413),
and the aforemenoned background numbers from cur-
rent surveys, these factors which are suggested to nega-
vely aect health would be relevant to about 86 – 94%
of the public and of parcular interest for athletes.
Plant protein low-grade quality or benecial to
heart health and muscle: Even today, meat remains
presgious and a symbol of masculinity especially
among men and athletes [2] (pp. 392, 396, 397), [166].
The convenonal male archetype or even male role
concepts are associated with physical performance
(capacity), strength, potency, dominaon, and power
[166-168]. The renunciaon of meat and animal prod-
ucts could lead to male vegans in parcular not being
considered socially as ‘real’ men, especially in the per-
cepon of the athlete`s peer group. Not to fulll this
stereotype could lead to social isolaon and exclusion,
which in turn could result in a reducon in self-esteem
[169]. This issue might be especially relevant in sports
and relates directly to the acceptance of (male) vegan
athletes. Therefore, protein constutes a much debated
issue in both the public and sports [163] (p.66), [170].
Although the health benets of vegan diets are
sound, the prevailing opinion that plant protein is low-
grade is a sll widespread belief. This is why vegans are
repeatedly asked with subliminal prejudices, namely:
´Plant protein is of inferior quality, isn`t it?´, and ´Where
do you get your protein from?´.
Protein is a key for building and maintaining the
body’s ssues, and necessary for promong the repair
and renewal of damaged ssue, including muscle. Except
for fruits, many plant foods are high in protein, such as
soybeans and lupins, peanuts, potatoes and rice, which
contribute about 40%, 25%, 8% and 8% of total energy,
respecvely. On a caloric basis, many plant foods are in
fact higher in protein content than animal foods (high
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Nowadays, when protein deciency occurs, it almost
always results from inadequate energy intake (in poor
regions such as developing countries) and not from the
consumpon of protein of inferior quality [163] (p. 65).
Most people in industrialized regions (eg. Europe, USA)
are oversupplied with (animal) protein and thus get suf-
cient protein and even levels exceeding the Recom-
mended Dietary Allowance (RDA) level of total protein
intake [67] (pp. 4, 82, 96), [163] (p. 67).
Considering the so-called potenally crical nutri-
ents (vitamin B12, vitamin D, iron, iodine, calcium, zinc,
long-chain omega-3-fay acids), vegan diets in parcu-
lar have been formerly described as decient [83] (pp.
229-234). However, some of these nutrients (calcium,
iodine, iron, vitamin D, zinc) are not only key for veg-
ans, but crical for omnivores and vegetarians, too.
Also, long-chain omega-3-fay acids as well as vitamin
B12 have been shown to be not exclusively crical to
vegans. Long-term supply of vitamin B12 can safely be
provided by fored foods and products (ie. plant milk,
tooth paste) and even supplements [85] (p. 121). In this
context, it is noteworthy to menon that vitamin B12
deciency is common and not infrequently detected in
older omnivores (reduced absorpon, drug ingeson
such as inhibitors to gastric acid). Since it is generally be-
lieved, also amongst physicians, that vitamin B12 de-
ciency does not exist in meat-eaters, vitamin B12 blood
levels are usually not checked, to the paents´ disadvan-
tage. As a consequence, it then oen goes undetected
[85] (p. 121).
Due to the low intakes of protein and calcium (see
Table 3) vegetarian and vegan diets are expected to
cause low bone mineral density and osteoporosis. De-
pite this, the bone health of vegetarians and vegans is
good. The very low or absent dietary acid load resung
from vegetarian and vegan diets - linked to a high intake
of potassium from potassium-rich foods such as fruits
and vegetables - reduces bone resorpon and promotes
bone formaon (higher density), and might be an im-
portant factor for the protecon of vegetarians from
osteoporosis. Bone mineral density is not decreased in
vegetarians and in most vegans [146,188], and concerns
regardering an increased risk of osteoporosis, and thus
fracture, is unsubstanated, except for vegans who con-
sume parcularly lile calcium [146].
Generally, nutrient deciencies (eg. iron, iodine, vi-
tamin D, vitamin B12) occur in all dietary paerns, in-
cluding mixed diets [26,189], [2] (p. 411). Thus, vegan
diets are nutrionally not more decient than any other
kind of diet [190]. In terms of daily intake, in line with a
brief review that found seven nutrients (calcium, ber,
folic acid, iodine, magnesium, vitamins C and E) were
decient with a mixed diet [191], a recent study found
that omnivores on average do not meet the recom-
mended daily intake of six nutrients (calcium, copper,
folate, iron, magnesium, vitamin E) [192]. In vegetarians
duced resng heart rate) over a lifeme is suggested to
increase lifespan by 13 years [181].
In general, athletes have lower resng heart rates (≤
60 bpm) than non-acve people, with lower resng heart
rates correlang to higher tness levels [180]. In theory,
without physical exercise one could increase lifespan
by about one decade or more (maximum lifespan by 1
beat/second) [179] by reducing the resng heart rate to
the same level as athletes’, just through eang legumes
and pulses amongst other plants. The daily intake of one
cup of beans, chickpeas or lenls over 90 days has been
shown to reduce the resng heart rate (-3.4 bpm) by the
same amount as exercising for 250 hours on a treadmill
[182]. With regards to a healthy heart being an essenal
prerequisite for an athlete’ s peak performance, a cur-
rent meta-analysis has found that a vegan diet is asso-
ciated with a more favorable cardiometabolic prole, in
contrast to that of a mixed diet [27,85,87].
Overall, the claim that vegan diets are inadequate to
promote health due to “poor-quality plant protein” and
“insucient amounts of protein” can no longer be upheld
[2] (p. 399). Thus, the concern that especially vegan ath-
letes might not consume adequate quality and amounts
of protein is unsubstanated [26,88,173,175,183,184].
Overall, vegan diets constute an opmal basis for par-
cipaon in sports.
Benet-Risk-Rao of vegan diets as a tool for ath-
letes
A good or even maximum state of health is not only
relevant to but also a crucial condion for sporng
performance and athlec success. Therefore, from an
athlete´s perspecve, rang the benets and potenal
risks that might emerge from a vegan diet can be helpful
when deciding whether to put it into pracce in sports
(school, training, and racing) or not.
Current scienc evidence has resulted in a trans-
formed rang of vegetarian and vegan diets, inially from
a prejudiced perspecve [185], then to quesoning their
adequacy, then to being equal to convenonal diets [85]
(pp. 49-50). Growing scienc interest is now focusing
on associaons with promong opmal health [163] (p.
5), and their impact on sports performance. Today, the
posive and negave eects of vegetarian kinds of diet
on health are well-known. The cumulave ndings show
that well-planned vegan diets are more health-promot-
ing and less harmful to health than convenonal diets,
with the health benets of vegan diets clearly exceeding
the potenal risk. However, the ever-growing body of
scienc data provides a signicantly broader basis in
favor of vegan diets, showing that the benecial eects
of vegan diets by far outweigh potenal detrimental ef-
fects [86,133,134,186], [85] (pp. 49-50). Since diets like
the wholesome plant-based diet, including vegan kinds
of diet, have been extensively studied, they have been
convincingly proven to be suitable as permanent diets,
and are recommended for connuous adherence [187].
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122-123).
Recent results from the Global Burden of Disease
Study [195] showed dietary risks account for 22% of all
deaths among adults globally, with > 50% of diet-relat-
ed deaths caused by poor dietary habits mainly charac-
terized by insuciency due to low intakes of fruits and
whole grains (but high of sodium). A nutrient-dense
vegan diet rich in wholesome foods including grains,
legumes, nuts, fruits and vegetables is a sound, evi-
dence-based recommendaon, and thus should be ad-
vised as a healthy opon [26]. Adopng a wholesome
vegan diet high in nutrient-rich, fresh, organic foods,
preferably combined with unprocessed foods, that is
carefully planned and diligently implemented in an ath-
lete’s everyday schedule, creates advantageous condi-
ons for maximum health and performing at one´s best
[147], [2] (p. 401).
Advantages to Sports Emerging from Vegan
Diets - Prerequisites for Successful Athletes
The healthy human is only the prerequisite for the
successful athlete. Achieving the cumulave health ben-
ets that emerge from the permanent and inter-related
applicaon of both the key lifestyle factors - a (whole-
some) vegan diet and (daily, moderate) sport and exer-
cise – might be relevant to the acve people and recre-
aonal athletes in general, but are even more important
in ambious, professional and top level sports. Gener-
ally, a conscious change in an athletes’ perspecve on
health has the potenal to iniate an advantageous par-
adigm shi in the behavior considering sports nutrion
and performance.
According to the ADA [174], “athlec performance
and recovery from exercise are enhanced by opmal
nutrion”, and thus “recommend appropriate selecon
of food and uids, ming of intake, and supplement
choices for opmal health and exercise performance.”
The American College of Sports Medicine (ACSM) [174]
and vegans, however, the daily intake was insucient in
three nutrients (calcium, zinc, vitamin B12) [192], with
vegans being decient in iodine instead of zinc [191].
Furthermore, it is known that vegans on average are
beer supplied with some nutrients, such as beta-car-
otene, vitamins C and K, folic acid, magnesium, potassi-
um, ber and phytochemicals. For other nutrients, such
as vitamin E, thiamin, bion and pantothenic acid, sup-
ply is equal to other kinds of diet [85] (p. 121).
Numerous studies have recently demonstrated that
in most, if not all cases, the observed deciencies usually
emerge from poor applicaon, i.e. by misapplied dietary
behavior [86,133,134]. The nutrional adequacy of any
parcular kind of diet, including the vegan diet, depends
on personal nutrional knowledge, how to appropri-
ately compose and prepare, and also how to diligently
supplement one’s diet [86,92,133,193,194]. Some stud-
ies have found that vegans either do not know how to
compose and prepare a whole food vegan diet, or do
not apply this knowledge. In these specic cases, sig-
nicant risks exist resulng from personal misbehavior,
but these cannot be extended to the vegan diet per se
[26,85] (p. 120).
It is generally accepted that with a well-composed
wholesome vegan diet appropriately supplemented by
vitamin B12 there are no risks for any age or any pro-
fessional group [85] (p. 121), including athletes. There-
fore, since potenal deciencies can be easily avoided
[26], a vegan diet lacking any deciency can result from
careful planning, appropriate composion and prepara-
on, and with adequate supplementaon, when energy
needs are met [26,31,88]. However, with the threat of
dangerous half-knowledge is also persistent and oen
widespread, there is an obvious contradicon, because
sciencally proven reality is turned upside down when
discussions lack evidence and thus rate vegan diets as
eg. unhealthy, which seems inappropriate considering
the substanal evidence-based data available [85] (pp.
Table 3: Overview of macronutrient distribution (A) following current guidelines considering meal composition of conventional
mixed diets (as percentage of total energy intake (%)); and (B) macronutrient distribution from individual surveys (2000-2009) for
omnivores, vegetarians and vegans, and from a meta-analysis of observational studies (1984-2017) of vegans versus omnivores
(as percentage of total energy intake (%) and as mean value including range (min-max)).
Carbohydrates (%) Protein (%) Fat (%)
Current guidelines (A)1
EFSA 45-60 12-20 20-35
IOM 40-65 10-35 20-35
Intakes from individual surveys (B)2
Vegan 50-65
(53.8-69.1)
10-12
(8.2-13.5)
25-30
(18.4-33.2)
Vegetarian 50-55
(51.0-68.0)
12-14
(8.4-15.3)
28-34
(20.0-36.9)
Omnivore ≤ 51
(44.0-64.9)
14-18
(8.8-17.9)
34
(23.4-37.1)
1[175,212-214]; 2[87], [163] (pp. 14-15, 464-468)
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populaons, too.
In addion, current ndings from the NURMI Study
(Step 2) showed 91 vegan runners (of total 245) to be
more health-conscious than non-vegan runners [24].
Overall, within eight dimensions of health status in en-
durance runners, the vegan dietary subgroup contribu-
on to runners’ good state of health ranged from 61%
– 91%. With 75% (± 20%, p = 0.001), showing the highest
scores within the food choice dimension, they reported
choosing food more oen because it is good for main-
taining health (95%, p = 0.05), choosing it more oen
to obtain specic ingredients, eg. phytochemicals (59%,
p = 0.007), and even to avoid specic nutrients such
as sweeteners (80%, p = 0.046), saturated fats (72%, p
= 0.007) and cholesterol (65%, p < 0.001). Conclusive-
ly, vegan endurance runners were found to contribute
most benecially to their overall state of health, mainly
because they reported to be extraordinarily health-con-
scious, in parcular due to their food choice behavior.
In line with a recent study performed on ambious rec-
reaonal runners in the laboratory [196,199,200], these
ndings support the noon that adhering to a vegan di-
etary paern is compable with ambious endurance
running [24]. Further results from Step 2 showed vege-
tarian and vegan endurance runners had a high quality
of life, like the omnivorous runners, too [21].
However, athletes may reach the point in their ca-
reers when it becomes necessary to search for alterna-
ves and possibilies to further develop or completely
tap their athlec potenal. Some take pills and/or pow-
ders while others switch to a vegetarian or vegan diet
in order to gain advantages in both training and racing,
beneng post-exercise recovery and regeneraon,
and to enhance total performance capacity [201].
From the authors´ experience, not only among the
normal populaon but also frequently with athletes and
their coaches, nutrional knowledge is oen alarming-
ly poor. In their quest to be extraordinarily well fueled,
along with their belief in consuming high quality foods
and nutrients to gain superior health, athletes oen in-
ict harm on themselves through detrimental nutrion
and suspect fueling pracces, rather than nourishment
for beer tness and peak performance [2] (p. 436).
Characteriscs of whole food vegan diets that aid
athlec performance
Based on the characteriscs of plant foods, the na-
ture of the vegan diet is especially unique compared
to non-vegan diets. The nutrient-dense, high-carbohy-
drate, high-ber, but low-fat (inclusive saturated fay
acids) and thus low-calorie, and zero cholesterol nature
of vegan diets is especially characterisc. In general,
a complete wholesome vegan diet is rich in nutrients
due to high intakes of vegetables and fruits, legumes,
soy products, whole grains, nuts and seeds (respecve-
ly rich in ber, phytochemicals and vitamins). The high
highlights in their current joint posion statement, that
“the performance of, and recovery from, sporng acv-
ies are enhanced by well-chosen nutrion strategies”.
Therefore, they provide nutrion guidelines to support
opmal health and athlec performance, spanning from
training to racing.
Even aer decades of research focussing on the ef-
fects of vegetarian diets on health, knowledge is sparse
about if and how veganism aects athlec performance.
Despite the abundance of evidence on the health ben-
ets that emerge from parcularly vegan diets [88],
whether a vegan diet per se promotes athlec (peak)
performance or not is sll unclear and remains to be de-
termined [11,12,101,196].
There is ample evidence from laboratory and eld
studies demonstrang that a well-planned vegetari-
an and vegan diet can meet the energy and nutrional
needs of compeve athletes [95]. Since well-planned
vegan diets are healthy and nutrionally adequate,
even for athletes, the ACSM [173] emphasizes that veg-
an diets can even meet the increased nutrional needs
of compeve athletes when energy requirements are
met, and when they contain high levels of vegetables
and fruits, nuts, whole grains, soy products, dietary ber,
anoxidants and phytochemicals [26,31,101,102,105].
A vegetarian or vegan diet was rst recommended in
1982 as the ideal dietary strategy for athletes but most
eecve for endurance athletes (eg. runners, cyclists,
triathletes) [48], even though informaon about (strict)
vegetarian diets linked to athlec performance had
been sparse, if it existed at all. 32 years aer the inial
recommendaon, Austrian researchers documented for
the rst me the successful implementaon of vegan in-
race dietary taccs in ultra-endurance sports [20]. Aer
eight consecuve stages of the Mountain Bike Transalp
Challenge 2004, which was shown to be physiological-
ly very demanding [197], the nal performance on a
high-carbohydrate vegan diet was +20% beer than ex-
pected. Moreover, the vegan athlete was able to main-
tain an average speed of 15.6 km/h resulng from an ex-
ercise intensity of 88% of race induced maximum heart
rate (80% of laboratory determined maximum) over the
full stage race, with respecvely 95% and 83% of in-race
and total energy coming from carbohydrates [20].
Since there is no proof to suggest that a vegan diet per
se can improve human performance [11,12,101,196],
research about the eects of long-term or even lifeme
adherence to veganism in athlec performance is sll
limited to only two case studies performed on vegan ul-
tra-endurance athletes. Together, these data show that
vegan athletes are not only compeve (physiological
prole, race results), but further match the exercise-in-
duced nutrional demands of prolonged high intensity
training and racing [20,198]. These results suggest that a
carefully planned vegan diet diligently put into pracce
can be eecve for other athletes and specic athlec
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animal foods. This is due to much lower contaminaon
by health threatening noxious and toxic substances as
well as their residues resulng from absorpon (rao of
1:9 from drugs, toxins and heavy metals, along with a
rao up to 1:14 from pescides) [154-156,165].
The strong alkalizing nature of vegan diets
might not only have a posive impact on health
[141,144,146,188,204], but also serves as a prerequisite
for performance of exercise, especially at high intensi-
es, too. Since non-acve vegans show beer metabolic
parameters than non-vegans [209], vegan athletes will
benet even more from this opmal baseline metabol-
ic status, prior to any single unit of training or racing.
As a basis for performance, they lack other negave ef-
fects of non-vegan diets (eg. saturated fats, cholesterol,
purines, and residues) that would reduce the ability to
perform [2] (p. 400). However, compared to a high acid
promong diet, an alkaline promong diet with a mark-
edly low acid load was shown to increase anaerobic ex-
ercise me to exhauson during high intensity treadmill
running by +21%. This was calculated to translate to a
10-mes higher reducon in dietary acid load, which
is associated with an increase of approximately 5% (6
seconds) [141]. A current study showed an increased di-
et-induced blood buer capacity (base excess, bicarbon-
ate concentraon), although anaerobic performance
was unaected [210], which may in part be due to the
dierent diets pre-exercise metabolic state [18,211].
Moreover, the posive relaonship between intake
of specic nutrients (eg. macronutrients such as com-
plex carbohydrates; micronutrients such as zinc; anoxi-
dants like vitamins C and E, polyphenols, beta-carotene)
and vegetarian kinds of diet with immune funcon is ev-
ident. Nutrional modulaon can play a role in mediat-
ing immunological eects with the opmum diet to best
support immune defense to prevent chronic inamma-
on and infecons [17,18,137]. Together, low-fat whole
food vegetarian diets, but especially vegan diets, ben-
ecially inuence inammaon, immune funcon and
anoxidant status by modulang the inammatory and
immune system (elevated biomarkers). Recent evidence
indicates such diets to improve (signicantly lower)
levels of serum C-reacve protein (CRP), brinogen, in-
terleukin-6, and total leukocyte concentraons, as well
as lymphocyte responsiveness and natural killer cell
funconality [17,18]. These advantageous but subtle
changes provide posive health outcomes and suggest
improvements that translate into benets for endur-
ance athletes that may result from an opmized intake
of phytochemicals (parcularly polyphenols) and unre-
ned carbohydrates, with low intakes of choline, beta-
ine, carnine and saturated fat at the same me [18].
Together, these facts are fundamentally advanta-
geous to vegan athletes, as they might posively aect
exercise performance during training and racing, and
likely constute a good prerequisite for sport and peak
ingeson of ber due to the high intakes of plant foods
results in rapid saety and thus decreased total energy
intake, which aids in the reducon of BW by reducing
of body fat mass [13,16]. Therefore, several indexes
that have evaluated overall nutrion relang to healthy
eang have rated vegan (vegetarian) diets as typically
beer (highest scores) than mixed diets (lowest scores)
[26,88,202], (p. 79).
The key benets to vegan athletes compared to
non-vegan foods and products are the higher intakes
of complex carbohydrates, dietary ber (only present
in plants), anoxidant vitamins C and E, folic acid, mag-
nesium, potassium and sodium, carotenoids and other
phytochemicals [26, 86, 88, 147, 177], [83] (p. 190).
In general, specic food items markedly aect the
metabolic regulaon of the organism by changes in the
acid-base balance with vegetables, fruits and potatoes
(low-PRAL food items) having the highest alkalizing po-
tenal [138,139,141,144,146]. While average values of
calculated dietary acid load for specic fruits and veg-
etables are down to -23 mEq/day [203], milk and yo-
gurt are of about +1 mEq, and meat, sh, poultry, egg
and even some grain products of ≥ +7 mEq [204], with
cheese alone ranging from +26 -34 mEq/day [145]. The
pronounced alkalizing (low-PRAL) character of vegan di-
ets increases bases by high intakes of fruits and vegeta-
bles that generally pose the lowest acid load [205] and
reduce acid excreon [141,144,146,188,204]. Conse-
quently, comparing the alkaline load of a typical vegan
meal (-22.9 mEq) or even vegetarian meal (-10.9 mEq)
to the acid load of an omnivorous meal (+41.7 mEq), the
metabolic burden is calculated to markedly dier (64.6
mEq) [142,145]. Thus, not suprisingly, a markedly dier-
ent metabolic burden was found for vegan (-15.2 mEq/
day up to -39 mEq/day), vegetarian (-1.5 mEq/day), and
omnivorous diets (+19.6 mEq/day) [188,206]. This is in
line with the mean net acid excreon values found to
signicantly dier for vegans (17.3 mEq/day), vegetar-
ians (31.3 mEq/day), and omnivores (42.6 mEq/day)
[207].
However, because diet and exercise alone may af-
fect acid-base balance, and thus pH-value [208], their
combined impact is relevant to both anaerobic and
aerobic exercise performance. During sports, the exer-
cise-induced physical stress challenges an athlete’s me-
tabolism through complex demands (eg. gas-exchange
capacies, buering enhanced accumulaon of blood
lactate and hydrogen ion levels reducing the pH-value).
Resulng from the digeson and the break-down of
foods and nutrients from animal sources, the organism
has to compensate for harmful substances in addion
to catabolic products (e.g. nitrogen, sulfur-containing
substances) and low-grade metabolic acidosis resulng
from higher dietary acid load [146], which together pose
another heavy burden on the exercise-induced metab-
olism. In addion, the physiological burden on the ath-
lete’s organism is markedly less for plant foods than for
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involved in heavy training regimens to achieve their in-
creased carbohydrate needs of up to ≥ 80% of total en-
ergy in order to maintain stable body glycogen stores.
Carbohydrates supply most of the energy required
during sport and exercise which is high in both extent
and intensity [216] (p. 412), and can improve race per-
formance [217-221] even at heat [222,223] and exercise
intensies > 80% of maximum performance, when large
amounts of energy must be provided over long periods
(> 90 min) [224-227]. Moreover, pre-exercise or ta-
pering as well as post-exercise and, more importantly,
post-race dietary strategies should focus on carbohy-
drates since they are crucial for opmum performance,
recovery and maximizing glycogen resynthesis. Howev-
er, Close, et al. [228] emphasize that not fat or protein
but carbohydrate is the dominant fuel for physical per-
formance during both extensive and intensive exercise.
In addion to endurance sports, they conrmed the
importance of carbohydrates to other types of athletes
such as rugby-players [228-230].
Sport and exercise cause changes in macronutrient
distribuons that are characterized by a more pro-
nounced shi to higher energy provision from carbo-
hydrates (markedly lower from protein and fat). Since
exercise-induced energy expenditure is elevated, en-
ergy from carbohydrates becomes increasingly import-
ant during prolonged high-intensity races (higher chal-
lenges to thermoregulatory and metabolic systems),
and is even more increased the more intense and the
longer the event. As a consequence, a macronutrient
rao of carbohydrates, protein and fat of up to 8:1:1
or, expressed as a percentage of total daily calories, of
80:10:10 occurs. Figure 1 shows this general shi to high
proporons of carbohydrates to contribute to total en-
ergy.
As is common during intensive racing in heat, the
increase in energy expenditure is managed by an even
higher need for carbohydrates [19,20], which should
be reected on the plate when planning an athlete´s
diet, and when composing and preparing meals [2] (p.
432). Therefore, a minimal carbohydrate to protein rao
[231] of at least 4:1 is advised for meal composion [2]
(p. 405). Drawn from the data of individual intakes pre-
sented in Table 3B, the carbohydrate to protein rao of
5:1 in vegans nicely matches this recommendaon and
provides opmal condions for promong an athlete’s
long-term health and exercise performance, while the
omnivores’ rao of 3:1 seems insucient. Moreover,
the rao of ≥ 8:1 in non-athletes is suggested to benet
health [2] (p. 405), [84] (pp. 25-78), [232] (pp. 83-113),
with up to ≥ 8:1 in athletes having been shown to op-
mally promote race performance in ultra-endurance
stage events [20].
To sum up, the quote “carbohydrate remains king”
[228-230] succinctly expresses the fact that carbohy-
drates not only constute the most important fuel for
performance, too. As vegan diets overall are considered
the healthiest kinds of diet [94], vegan athletes are able
to achieve opmal eects in order to develop an ath-
lete’s overall potenal through training and recovery,
and then to tap into it fully during races [2] (p. 401).
Macronutrients to fuel for sports
In order to maintain the numerous funcons of the
human organism, including respiraon, circulaon,
sport and exercise and protein synthesis, energy needed
is provided by the macronutrients carbohydrates, pro-
teins and fats [175] (p. 4).
The recommended macronutrient intakes contrib-
ung to daily calories reecng a convenonal dietary
paern [176,212-214] are presented in Table 3A. In ad-
dion, Table 3B presents the macronutrient distribuon
for vegans, vegetarians and omnivores, derived from in-
dividual surveys, showing that omnivores’ intakes con-
tribute considerably more energy from protein and fat,
especially when compared to vegans (+11% mean daily
energy intake, +27% protein, +25% fat). The daily carbo-
hydrate intake is highest in vegans, and lowest in omni-
vores (≤ 51%) [87,163] (pp. 14-15) with an evident but
inadequate carbohydrate contribuon of only 40-45%
of total energy intake found in many Western civiliza-
ons [215] (p. 181).
Considering dietary recommendaons for the
non-acve general populaon, a recent study on recre-
aonal runners found that carbohydrate intake of omni-
vores (46.7%) is lower than recommended (> 50%) and
signicantly diers from the adequate carbohydrate
intakes (55.5%) of vegans, along with protein intake of
vegans (1.25 g/kg of BW) exceeding recommended lev-
els (0.8 g/kg of BW). It was concluded that vegan rec-
reaonal athletes gain advantages over omnivores and
vegetarians [200].
Carbohydrate is the dominant fuel: Considering
their dominance in energy supply, carbohydrates have
always been of superior importance amongst all nutri-
ents of the human diet [215] (p.181). However, despite
their overriding role, carbohydrates have been, and sll
are today, usually neglected, while protein is overrated
[2] (pp. 397,402). It is evident that carbohydrates are
ulized by the body most eciently and thus constute
not only the preferred fuel at rest. Typically, complex
carbohydrates contribute the majority of a vegan’s en-
ergy intake. Non-acve vegans not only match the mac-
ronutrient guidelines but also meet the even higher
recommendaons for athletes as well as their in-race
energy needs (Table 3 and Figure 1).
By the early 1980s vegetarian dietary paerns were
already being recommended as parcularly eecve for
meeng high energy and carbohydrate demands [48],
especially for endurance athletes [47,183]. This is due
to the carbohydrate-rich characterisc of plant foods,
and since vegetarian diets can help endurance athletes
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Wirnitzer. Int J Sports Exerc Med 2020, 6:165 • Page 15 of 32 •
quadriceps) were observed [178]. Independent of di-
etary paern, the daily protein intake (57% from animal
sources, 43% from plants) of well-trained athletes ac-
ve in strength, endurance and team-sport (n=553) was
found at > 1.2 g/kg, which matches the exercise-induced
recommendaons. However, the distribuon over the
course of the day was found lower than recommended
(< 20 g) with 58% of athletes failing to distribute enough
protein at breakfast, 36% at lunch and 8% at dinner) and
inappropriate to maximize the skeletal muscle adapve
response to training [240]. Independent of the habitual
dietary roune of recreaonal athletes (vegetarians or
vegans (n=18) vs. omnivores), creane supplementaon
during an 8-week resistance exercise training increased
intramuscular IGF-I concentraon [239]. In addion,
for an increase of 10 g/day of vegetable protein, but
not animal protein, a signicant increase in distance
walked was recently found (+20 m in a 6 min walking
test), suggesng plant protein to benecially aect ex-
ercise performance in non-acve subjects [241]. More-
over, oat protein was found to be protecve considering
the negave eects of eccentric exercise, parcularly
against muscle damage induced by downhill running, as
it markedly diminishes muscle soreness, reduces mark-
ers for muscle damage (serum creane kinase, myoglo-
bin) and inammaon (plasma IL-6, CRP levels), and aids
in recovery from downhill running in untrained subjects
[242].
However, preserving skeletal muscle mass is import-
ant to maintain metabolic health and funconal capac-
the nutrional foundaon of health, but are also of even
more signicance to successful athletes, since carbohy-
drates are key at high metabolic rates and promotes
exercise performance. Resulng from this, any athlete
should fuel primarily by carbohydrates - even strength
athletes [231,232-235] -, with at least 50% of daily en-
ergy, or even 60-65% to meet the energy needs consid-
ered by sports nutrion recommendaons [236]. This is
easy to achieve through the high-carbohydrate nature
of a vegan diet.
Protein for vegan athletes to build muscle mass
and strength: Unl today, protein has been overrated
in general, and by men and athletes especially, with the
majority scking to the erroneous assumpon that ‘man
requires meat’. Mainly power and strength athletes sup-
port and pracce the predominant paradigm that the in-
take of large amounts of protein is paramount for build-
ing muscle mass and strength [2,237,238], (pp. 397,
402-403). Protein remains a symbol of bodily potenal
and vigor, therefore athletes in parcular are always
concerned about geng enough high-quality protein
[163] (p. 65) to build muscle.
In contrast, some recent studies support the fact that
the origin of protein is not decisive for building healthy –
strength or endurance-compable – muscles to success-
fully parcipate in power or endurance sports [178,239-
242]. Across six protein food clusters (‘fast food/full-fat
dairy’, ‘sh’, ‘red meat’, ‘chicken’, ‘low-fat milk’, and
‘legumes’ including also nuts/seeds/fruits/vegetables),
no dierences in muscle mass or muscle strength (m.
Figure 1: Comparison of macronutrient distribution by intake based on individual surveys of non-active normal populations:
(1) Omnivores, (2) Vegetarians, and (3) Vegans, against exercise-induced macronutrient distribution of athletes in ultra-
endurance stage-races: (4) Vegetarian ultra-runners during the Deutschlandlauf 1987, (5) Vegetarian supermarathon
runners (Schatalova experimental group), and (6) Mountainbike Transalp Challenge 2004. CHO – carbohydrate.
1,2,3[87], [163] (pp. 14-15); 4[283]; 5[55] (pp. 18-20, 51-52, 60, 64, 160); 6[20].
ISSN: 2469-5718DOI: 10.23937/2469-5718/1510165
Wirnitzer. Int J Sports Exerc Med 2020, 6:165 • Page 16 of 32 •
since current research is generally lacking regarding the
impact on athlec performance from long-term adher-
ence to veganism [170,173,174,244].
There are only two case studies performed on long-
term (> 5 years) vegan ultra-endurance athletes, both
indicang that muscle mass and strength matches the
performance of omnivorous counterparts [20,198] as
well as muscle health of non-acve people [178]. There-
fore, undesired facts that might be due to eg. misin-
formaon, inadequateness or failure in sports-specic
dietary or training strategy can result in dramac disad-
vantages to an athlete´s health and sports performance,
but cannot be aributed to the vegan diet per se.
Yet, the most frequently asked queson addressed
to vegan athletes is sll loaded with severe doubt, and is
namely: ´How do you meet your protein needs?´ The In-
ternaonal Society of Sports Nutrion (ISSN) [249] con-
cluded in their posion paper on protein and exercise
that evidence to date lacks proof about whether protein
quality from animal or plant origin is superior in terms of
opmizing recovery and/or training adaptaons.
Because only up to 5% of the sport- and exercise-in-
duced energy needs can be covered by the body’s pro-
tein stores [11,58], and contrary to common belief,
protein is not the predominant fuel. However, during
extraordinary metabolic situaons such as starvaon or
extreme BW loss due to dietary intervenons, proteins
can be catabolized and used as an emergency fuel to
supply energy to the body from internal sources, such
as from muscle mass or even from the quanty of en-
dogenous protein present in the gut which may be much
greater than that ingested [162,163] (p. 76).
The amount of physiological protein required by
non-acve people is 0.66 g/kg*day of BW, with the RDA
of 0.8-0.83 g/kg*day of BW (safety margin for variaons
such as illness included) [175,214], being markedly high-
er (+25%) than the needs. A slightly higher gure than
this protein intake is recommended (1) Due to the po-
tenally 10% lower protein digesbility of vegetarian
diets of up to 1.0 g/kg of BW, and (2) Another approxi-
mately 25% increase for those vegans who either might
not consume a diet containing a large range of various
protein sources but who mainly ingest plant proteins
with a very low digesbility, like beans [174,250], [163]
(pp. 66-67).
The guidelines for daily protein intake for endurance
and strength-trained athletes outline a range of 1.2-1.7
g/kg*day of BW [174], which is supported by protein ex-
perts considering an athletes’ requirement (1.2-1.8 g/
kg*day) [237,251]. Because of the aforemenoned low-
er digesbility of plant proteins, a higher protein intake
that equals the respecve value of 1.3-1.8 g/kg*day of
BW is recommended for vegan athletes [174].
Although not all authories support higher pro-
tein intakes for athletes [174,175], some organizaons
ity [172,243]. Independent of kind of diet, total muscle
mass (including circumference of a specic muscle) can
be adapted by concrete intervenons that are decisive
to build muscle mass, eg. the appropriate training sm-
ulus as one crucial factor.
Not meeng the key requirements of adequate (1)
Energy intake, (2) Protein/amino acids intake, consider-
ing the amount and ming along with sucient carbo-
hydrate, and (3) High-quality protein (rather than kind
of source, eg. soy, rice, wheat, beef, whey, egg) can
result in (i) An undesired decrease in BW and muscle
strength due to loss of body fat and muscle mass, (ii) A
negave eect on health, and (iii) A negave impact on
athlec performance [20,170,173,174,231,244], [2] (p.
405), [84] (pp. 55-78), [232] (pp. 83-113). These aspects
inuence an athlete´s potenal to build and maintain
muscles that are compable to high-intensity and/or
long-term power and strength sports as well as endur-
ance sports, too.
Although, muscle mass alone as a predicve param-
eter to performance is not meaningful for rang the ap-
propriateness of specic kinds of diet in sports. To win
or lose depends on various performance-determining
factors within a specic prole of skills and capacies,
and is rather more complex than being limited to mus-
cle mass and/or strength. An athlete’s opmal physique
is related to factors such as age, sex and genecs [172-
174,243], and is linked to the specic demands of a giv-
en kind of sports or discipline.
However, among athletes, muscle mass is oen be-
lieved as the ulmate performance-determining factor,
especially in power and strength sports.
A vegan diet supposedly limits the gain of muscle
mass and strength, and long-term adherence is even
claimed to decrease muscle mass and negavely aect
muscle strength. Yet, there is anectodal evidence from
world records set by vegan power and strength, and
even endurance athletes (as well as their mere parc-
ipaon in Olympic Games and World Championships).
From the experience of mentoring and supervising
ambious (vegan) athletes from endurance to strength
sports for two decades, not one of them has reported an
undesired loss in muscle mass due to the vegan diet. In
addion, with the growing scienc interest especially in
vegan diets, there is special concern of the hypertrophic
potenal of a vegan diet following a resistance training
in terms of muscle mass and strength [172,243,245-248],
and even from evidence-based literature, this concern
is unsubstanated. Since no study performed on power
and strength athletes on long-term vegan diets exists, a
decrease in muscle mass and/or muscle strength on a
vegan diet sll remains to be proven. To date, no single
study has shown limitaons related to muscle mass and/
or strength that result from a (i) Well-planned, diligently
conducted (ii) Long-term (iii) Vegan diet (iv) In athletes,
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Wirnitzer. Int J Sports Exerc Med 2020, 6:165 • Page 17 of 32 •
nivores: 2213 ± 444 nmol/L); and vitamin D levels of
vegans (86.2 ± 39.5 nmol/L) were comparable to that
of non-vegans (vegetarians: 76.8 ± 33.7 nmol/L; omni-
vores: 90.6 ± 32.1 nmol/L), with low prevalence (< 20%)
of inadequate vitamin D. The authors concluded that
the benets emerging from a vegan diet (carbohydrate,
iron, ber) excel over omnivores and vegetarians for
recreaonal runners, and that a well-planned and sup-
plemented vegan diet can meet the athlete’s require-
ments of vitamin B12, vitamin D and iron [199,200].
Resulng from this, a well-planned and supplement-
ed, and diligently implemented vegan diet is compable
with compeve sport and promotes a good state of
health with no risk of developing nutrional decien-
cies [10,11,13,26,196,199,200,254], [254] (p.778, 788).
However, because non-acve vegans have to supple-
ment vitamin B12, it is necessary for vegan athletes, too.
Despite there being no need for any other supplemen-
taon when vegan diets are based on a big variety of
wholesome plant foods [2] (pp. 431-432), supplements
might add benets as part of an athletes’ dietary strat-
egy.
However, due to the greatly increased metabolic rate
from me to me, well-trained (compeve) athletes
generally show a markedly higher need for energy, all
nutrients, vitamins and minerals, as well for as other vi-
tal substances. As the respecve values can vary greatly
and depend on many factors such as training and racing,
among others, these exercise-induced needs exceed the
usual daily requirements and are therefore more di-
cult to cover by daily meals. Therefore, it is important
that all athletes – regardless of which kind of diet – have
to be aware of the fact that careful planning and diligent
implementaon of their personalized exercise-induced
diet into daily scenarios is essenal for coping with the
higher nutrional requirements. This is necessary in
order to avoid exercise and diet-related under-supply,
which would result in imbalances and/or deciencies
with negave eects on both health and sports perfor-
mance [10