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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
Citaon: Wirnitzer KC (2020) Vegan Diet in Sports and Exercise – Health Benets and Advantag-
es to Athletes and Physically Acve People: A Narrave 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 arcle distributed under the terms of the
Creave Commons Aribuon License, which permits unrestricted use, distribuon, and reproducon
in any medium, provided the original author and source are credited.
Vegan Diet in Sports and Exercise – Health Benets and Advantag-
es to Athletes and Physically Acve People: A Narrave Review
Katharina C Wirnitzer1,2,3,4*
1Department of Subject Didaccs and Educaonal Research and Development, University College of
Teacher Educaon Tyrol, Austria
2Department of Sport Science, Leopold-Franzens University of Innsbruck, Austria
3Research Centre Medical Humanies, University of Innsbruck, Austria
4Life and Health Science Cluster Tyrol, Subcluster Health/Medicine/Psychology, Tyrolean University
Conference, Austria
a fullled 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 sporng success
[2] (p. 401). The close connecon between health and
the lifestyle factors of nutrion 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 connuous inter-related ap-
plicaon is a highly eecve but simple tool for improv-
ing individual health, especially for athletes. Moreover,
because personal behavior (eg. food choices) has the
greatest potenal 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 publicaon of review ar-
cles on veganism in sports than ever before, which all
contribute to and reect the increasingly high scienc
interest in the linkages between a vegan diet and sport
and exercise.
Within a meframe of 16 years, between 2004 and
2020, nine review arcles considering plant-based diets
in relaon to sports have been released [9-18], with ve
addionally focused on vegetarian diets or to a lesser
REVIEW ARTICLE
Check for
updates
Abstract
Health is one factor in leading a fullled 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 benets 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-
ets 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 Didaccs and Educaonal Research and
Development, University College of Teacher Educaon Tyrol, Austria
Introducon
Health is a prerequisite for and one factor in leading
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plant-based diets in the public and in sports around the
globe while being much debated among sport sciensts
and sports nutrion 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 ancipated [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) populaons [35-37], 13% of the Brish [38] and
14% of the Swiss populaon (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 generaons, with the
so-called “millenials” (or “Generaon 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 Generaon 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 benets as the main reason (61%)
[44], and increasing numbers of the Baby Boomers gen-
eraon 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) starng in running events.
There are some professional vegan athletes who are
acve 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 compleng
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
lile informaon available. These reviews were mainly
based on studies performed on vegetarian non-acve
populaons or athletes, with ve focusing on nutrional
consideraons [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-
dion, no review has addressed the most basic prereq-
uisite for athlec (peak) performance, which is health
above all. Addionally, 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 benets resulng from a vegan diet to
athletes and the concept that it might provide advan-
tages for (young, compeve) athletes. In presenng
relevant informaon for both experts and praconers
in the eld of sports and physical educaon, 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 perspecve which cuts across
the three disciplines of diet, sports and health. This re-
view is also the rst to combine scienc raonale from
evidence-based data with relevant anecdotal informa-
on in order to support a more healthy approach to
sports nutrion counseling of athletes. Based on this sol-
id foundaon, the intenon is to nudge experts, ranging
from sports praconers such as coaches, dieans and
families to specialized sciensts in the elds of sports,
nutrion, 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 paern, including
a vegan diet.
Background
Nowadays, giving up meat and animal products is a
steadily growing trend, mainly in industrialized naons,
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
constute a current boom with increasing acceptance
and appreciaon 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,
recreaonal, amateur and professional sports.
The book Thrive: The Vegan Nutrion 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 reect 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-eang athletes needed [49,53].
In the 1980s, over a seven-year period of eld studies
(1983-1990) consisng of several series of super-mara-
thons, trekking tours at high altudes, and desert tra-
verses on foot [55] (pp. 18-20, 51-52, 60, 63-65, 159-
174), [56] (pp.19-20), the potenal that emerges from
following strict vegetarian (vegan) diets was demon-
strated, as well as the posive eects on physical per-
formances resulng from Galina Schatalova’s specic
dietary concept for metabolic eciency (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 beer than those
in the omnivorous control groups for all eld trials [55]
(p.161). The vegetarian hikers were beer able to cope
with severe physical stress and to sustain physical bur-
dens, even at high altudes 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 duraons, and to recover
from physical stress more rapidly. This supports the as-
sumpon 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 representave, the Greek Pythagoras was
not only a prominent philosopher and mathemacian,
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 eec-
ve and t. The gladiators followed a specic diet (‘glad-
iatoriam saginam’ or even ‘hordearii’) that consisted of
large amounts of legumes, pulses, and grains (78% from
peas, lenls, barley, wheat, millet, corn), but explicitly
with lile 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.
Dang back to even earlier in human evoluon, di-
etary behavior and habits have been associated with
physical and cognive performance [2] (pp. 409-410).
Based on Neanderthal ecology from genomic data
showing regional dierences, 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 representaves of
technical sports, such as Meagan Duhamel (pairs gure
skang; 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 Lier, Rio
2016; set the American record in the 94 kg weight class);
or Frank Medrano (Superhuman Bodyweight Workout
dominaon), 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 addion, in
2014 in Brazil the German Naonal Football Team won
the World Championship while temporarily adopng a
vegan diet.
These and numerous other successful athletes who
adhere to vegan diets provide sucient evidence that
for all kinds of sports, ranging from high-level endurance
and ultra-endurance to power and strength disciplines,
athlec success (victories, world records, etc.) can be
achieved when following a vegan diet. Therefore, it is
reasonable to conclude that a vegan diet is compable
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 aracted
scienc 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 inial scienc interest in vegetarian diets as
they relate to athlec 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. Dierent sciensts invesgated if and how
vegetarian diets inuence physical performance by con-
ducng 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 posive eects on exercise performance.
These inial data comparing strict vegetarian athletes to
meat-centered athletes (me to exhauson: On a sta-
onary bicycle, liing an external load by handgrip me-
ter, holding horizontal arm posion, 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]: Inuence 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 signicantly further, had higher BMI, higher fruit
intake, less alcohol
¾Dietary assessment was limited -> lack of data on other foods/specic 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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ambious endurance athletes are at signicant 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-promong
items (eg. ber, anoxidants) may contribute to arterial
changes that promote atherosclerosis [16]. This might
explain why endurance athletes more oen develop
severe atherosclerosis than non-acve people (high-
er values for coronary plaque: 44% vs. 22% total [68],
and (non-)calcied plaque [69,70]. Moreover, the carot-
id artery inma-media thickness has been found to be
signicantly 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-
tremies, which consequently negavely aects athlec
performance [16].
In this context, there is enormous potenal to make
an important contribuon to the abandonment of the
1-dimensional perspecve of health, whereby either
one of these lifestyle factors is usually viewed and im-
plemented in isolaon, namely: either nutrion or sport
and exercise [2] (pp. 418-419).
Dual guidelines on supporng good health have in-
extricably linked diet with sports and exercise recom-
mendaons since 2002. The goal has not only been to
avoid unnecessary body fat accreon 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 acvity 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 inacvity, and
overweight/obesity contribute to 13%, 9%, 6%, 6%, and
5% of global deaths, respecvely [65,66,74-78]. Based
on science-based recommendaons, the world´s lead-
ing nutrional, sports and health organizaons have
released guidelines which emphasize the importance of
permanently balancing diet with sport and exercise in
order to achieve beer individual health [2] (pp. 418-
419).
Therefore, in order to achieve beer health for ath-
letes, the foundaon 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’.
Aer more than 50 years of epidemiological studies,
it is accepted that cardiorespiratory tness, which re-
sults from both healthy acvity paerns and increased
levels of sports and exercise, leads to beer health [63].
A current study supports this by examining the eects 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 substanal benets emerge
from a lifelong adherence to aerobic exercise. In addi-
on to aerobic capacies 40% higher than their inac-
ve age-matched peers, the acve old subjects were
calculated to have the cardiovascular health of people
30 years younger than themselves when compared to
established data of capacies rated to be the norm [64].
It is generally accepted that sport and exercise are
powerful tools that posively aect health and thus aid
the prevenon of severe illnesses [65]. Regular sport
and exercise, at best on a daily basis, has been shown
to be prevenve 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 ulizaon, and thus for controlling Body
Weight (BW) [66].
However, physical acvity, sport and exercise as a
single mechanism for promong individual health and
aiding a healthy lifestyle are not enough, even when
pracced 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 suer from
(chronic) diseases. The following example exemplies
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
eang was not important. However, he died from a heart
aack during his daily jogging roune [67] (pp. 407-408).
A current study has found that even well-trained and
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health benets 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 oen 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 suer much less
frequently from being overweight and obese, and from
several other diseases [26,88,99]. Moreover, vegans are
more health-conscious (acve on a regular basis, no or
less consumpon of alcohol or tobacco) [85] (pp. 105-
106). Together, these aspects create the opmal basis
for improving an athlete`s performance.
The AND has declared in their current posion state-
ment [88] that well-planned vegetarian and vegan di-
ets are (1) Healthy, (2) Nutrionally adequate, match
dietary guidelines and meet current recommended in-
takes, (3) Provide health benets for the prevenon and
treatment of certain diseases, and (4) Are appropriate
for people at all ages as well as athletes. Seven of the
largest specialist associaons for nutrion worldwide
agree with the latest AND posions [100-107]. Howev-
er, there is a consensus that vegans have to take spe-
cial care to ensure a sucient supply of vitamin B12 by
reliable sources, such as fored foods or supplements
[26,88], [27] (pp. 48,102), [85] (p. 121).
Regarding the prevenon of diseases, the AND [26]
posion not only conrms, but also underlines and
explicitly highlights their former statement [85], that
“there are tremendous advantages toward prevenon
of chronic health condions by adhering to a vegetarian
eang paern”. The evidence-based literature proves
that vegan diets posively inuence the development,
prevenon, and therapy of chronic, inammatory, and
degenerave diseases. Regarding prevenve and ther-
apeuc diets, the vegan diet is highlighted as being
the most benecial diet [26,88] known to serve as an
eecve therapeuc tool in relaon 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 parcular ben-
ecially aects both BW control (overweight, obesity)
[26,90,93,95-99,108,115,127-129], microinammaon
[17,130], and chronic systemic inammaon [99].
Overall, the health benets of vegan diets are sound,
in addion 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
sporng performance and success, ranging from daily
parcipaon to winning medals Table 2.
moderate intensity on a daily basis – may oer the most
promising key intervenon for both an athlete`s sustain-
ably opmum 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 mulple mes in a day, a healthy vegan diet can
be easily and praccally applied to sports and various
sengs, if desired.
Vegan Diet - Foundaon for an Athlete’s Health
and Sporng Success
There is a consensus that diet, in addion to but
more important than sport and exercise, is the basic
foundaon 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,
holisc 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).
Nutrion 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 nutrional
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 scienc evidence, there is a growing in-
terest in and appreciaon 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-
teriscs of plant foods that there is a wide range of di-
et-related health benets from adopng vegetarian but
in parcular vegan diets [26,87,88]. Table 2 presents an
overview of the health benets resulng from vegan
(vegetarian) diets (without claiming to be complete).
Adequacy of vegan diets - benets to human health
The rst study ever performed on vegans which in-
vesgated their state of health, morbidity and mortal-
ity linked to chronic diseases was published in 1978
and showed disnct advantages of vegan diets over
non-vegan diets [89]. Two years later, in 1980, the Acad-
emy of Nutrion and Dietecs (AND, formerly American
Dietec Associaon: ADA) published its rst posion
statement on vegetarian diets. Since then, cumulave
evidence has repeatedly conrmed that vegetarians on
average are healthier than non-vegetarians.
Numerous reputable studies (e.g. Advenst 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 scienc literature available, the Physi-
cians Commiee for Responsible Medicine found that
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Table 2: Overview of the health benets resulting from vegan diets.
No. Health benets (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 benecial 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: specic 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 (signicantly lower) biomarkers of inammation and immune defense
(serum CRP, brinogen, interleukin-6; total leukocyte levels; lymphocyte
responsiveness; natural killer cell functionality)
↓ Less micro inammation and reduced chronic systemic inammation
↓ 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 fay 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
addion to protein, contain other components such as
sodium, nitrates and nitrites that are suggested to nega-
vely aect 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 contaminaon by toxic substances than products
derived from plant foods. These substances include
residues from pharmaceucal drugs (e.g. hormones to
increase growth, ferlity and lactaon, ataraccs, tran-
quilizers and anbiocs), industrial toxins (e.g. dioxins)
and heavy metals (e.g. lead or mercury) [2] (p. 400), and
higher levels of pescides (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 consumpon of animal foods (meat, sh and shell-
sh, and dairy products), compared to about 8% result-
ing from eang plant foods [155,156]. The exposure
to hazardous residues is detrimental to human health
[26,147], [2] (p. 400), and is parcularly detrimental to
an athlete`s state of health.
Evidence-based data has also shown frequent meat
(including sh and seafood) consumpon to be the ma-
jor risk factor for chronic disease [27] (pp. 105-107).
Disadvantages of red and processed meat consumpon
mostly result from the excessive intake of saturated
fats [157,158], along with other substances contained
in animal products, and result in an intensied risk of
Animal protein – detrimental to overall state of
health: A typical ‘Western diet’, also described as a
balanced mixed diet (generally dened 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 rened carbohydrates, together high in
‘empty’ calories, but with low intakes of vegetables and
fruits, dietary ber, micronutrients, and phytonutrients
(eg. polyphenols, omega 3 polyunsaturated fay acids)
[135-137]. The Western diet is a known risk factor for
metabolism-induced inammaon 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
specic kind of diet can markedly aect the metabolic
regulaon of the organism with its characterizing food
items, micronutrient prole, and capacity of acid or
base producon providing acid or alkaline precursors
inuences systemic blood acid-base status (pH-value)
and acid-base balance (eg. quaned by PRAL (mEq/100
g) - the potenal renal acid load) [144,146]. It is well
known that foods and dietary paerns rich in protein
(high-PRAL food items like eg. meat, cheese, eggs) in-
crease the acid producon and lead to high acid load
and systemic acidosis, while most plant foods have a
low potenal 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 buered mainly by increased bone resorpon, and
is associated with the development of metabolic alter-
aons and complicaons (eg. bone disorders negave-
ly correlated with bone mineral density, but posively
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 benecial 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 parcular 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 sucient amounts of all essenal
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 addional protein supplements
[176]. According to ample scienc evidence, both the
amino acid and protein needs of non-acve 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 nutrion agree that - when an
assortment of plant foods is eaten over the course of a
day – there is no need for nutrional behavior like in-
tenonal ‘protein combining’ or ‘complemenng’ when
composing and preparing meals in order to obtain all
the essenal amino acids, not even for vegan athletes
[26,31,177].
The Framingham Third Generaon Study has recent-
ly found that dietary protein is associated with muscu-
loskeletal health, independent of dietary paern [178].
Therefore, a vegan diet can equally contribute to muscle
health just like any other dietary paern.
Moreover, it is generally accepted that heart health
and resng heart rate, and thus cardiovascular health,
are highly aected by both diet and sport and exercise.
However, the evidence-based literature shows diet to
be the most powerful lifestyle factor in relaon to health
protecon and a healthy heart, even more than physical
exercise [179], [2] (pp. 390-391).
In a 16-year follow-up study, an increased resng
heart rate has been found to result in premature death
more frequently [180]. In addion, an increased risk of
premature death (+ 10 – 20%) has been found to result
from every 10 bpm increase in heart rate, with a resng
heart rate of > 65 bpm having a strong independent ef-
fect on premature mortality [179]. Therefore, a drop in
resng 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-
ciaon 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 protecve to health), the negave eects of red
meat consumpon on mortality (higher risk of all-causes
(+ 21%) and CVD (+ 29%)) were persistent and could not
be counteracted or compensated for [164].
Overall, the convenonal dietary paern is known to
cause severe health problems [136]. Therefore, despite
the claimed benets 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 aforemenoned background numbers from cur-
rent surveys, these factors which are suggested to nega-
vely aect health would be relevant to about 86 – 94%
of the public and of parcular interest for athletes.
Plant protein – low-grade quality or benecial to
heart health and muscle: Even today, meat remains
presgious and a symbol of masculinity – especially
among men and athletes [2] (pp. 392, 396, 397), [166].
The convenonal male archetype or even male role
concepts are associated with physical performance
(capacity), strength, potency, dominaon, and power
[166-168]. The renunciaon of meat and animal prod-
ucts could lead to male vegans in parcular not being
considered socially as ‘real’ men, especially in the per-
cepon of the athlete`s peer group. Not to fulll this
stereotype could lead to social isolaon and exclusion,
which in turn could result in a reducon in self-esteem
[169]. This issue might be especially relevant in sports
and relates directly to the acceptance of (male) vegan
athletes. Therefore, protein constutes a much debated
issue in both the public and sports [163] (p.66), [170].
Although the health benets of vegan diets are
sound, the prevailing opinion that plant protein is low-
grade is a sll 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 promong 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,
respecvely. 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 deciency occurs, it almost
always results from inadequate energy intake (in poor
regions such as developing countries) and not from the
consumpon 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 potenally crical nutri-
ents (vitamin B12, vitamin D, iron, iodine, calcium, zinc,
long-chain omega-3-fay acids), vegan diets in parcu-
lar have been formerly described as decient [83] (pp.
229-234). However, some of these nutrients (calcium,
iodine, iron, vitamin D, zinc) are not only key for veg-
ans, but crical for omnivores and vegetarians, too.
Also, long-chain omega-3-fay acids as well as vitamin
B12 have been shown to be not exclusively crical to
vegans. Long-term supply of vitamin B12 can safely be
provided by fored foods and products (ie. plant milk,
tooth paste) and even supplements [85] (p. 121). In this
context, it is noteworthy to menon that vitamin B12
deciency is common and not infrequently detected in
older omnivores (reduced absorpon, drug ingeson
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 paents´ disadvan-
tage. As a consequence, it then oen 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 resung
from vegetarian and vegan diets - linked to a high intake
of potassium from potassium-rich foods such as fruits
and vegetables - reduces bone resorpon and promotes
bone formaon (higher density), and might be an im-
portant factor for the protecon 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 unsubstanated, except for vegans who con-
sume parcularly lile calcium [146].
Generally, nutrient deciencies (eg. iron, iodine, vi-
tamin D, vitamin B12) occur in all dietary paerns, in-
cluding mixed diets [26,189], [2] (p. 411). Thus, vegan
diets are nutrionally not more decient 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
decient 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 resng heart rate) over a lifeme is suggested to
increase lifespan by 13 years [181].
In general, athletes have lower resng heart rates (≤
60 bpm) than non-acve people, with lower resng heart
rates correlang 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 resng heart rate to
the same level as athletes’, just through eang legumes
and pulses amongst other plants. The daily intake of one
cup of beans, chickpeas or lenls over 90 days has been
shown to reduce the resng 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 essenal
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 prole, 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
“insucient 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 unsubstanated [26,88,173,175,183,184].
Overall, vegan diets constute an opmal basis for par-
cipaon in sports.
Benet-Risk-Rao 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 condion for sporng
performance and athlec success. Therefore, from an
athlete´s perspecve, rang the benets and potenal
risks that might emerge from a vegan diet can be helpful
when deciding whether to put it into pracce in sports
(school, training, and racing) or not.
Current scienc evidence has resulted in a trans-
formed rang of vegetarian and vegan diets, inially from
a prejudiced perspecve [185], then to quesoning their
adequacy, then to being equal to convenonal diets [85]
(pp. 49-50). Growing scienc interest is now focusing
on associaons with promong opmal health [163] (p.
5), and their impact on sports performance. Today, the
posive and negave eects of vegetarian kinds of diet
on health are well-known. The cumulave ndings show
that well-planned vegan diets are more health-promot-
ing and less harmful to health than convenonal diets,
with the health benets of vegan diets clearly exceeding
the potenal risk. However, the ever-growing body of
scienc data provides a signicantly broader basis in
favor of vegan diets, showing that the benecial eects
of vegan diets by far outweigh potenal 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 connuous 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 insuciency 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 recommendaon, and thus should be ad-
vised as a healthy opon [26]. Adopng 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 cumulave health ben-
ets that emerge from the permanent and inter-related
applicaon of both the key lifestyle factors - a (whole-
some) vegan diet and (daily, moderate) sport and exer-
cise – might be relevant to the acve people and recre-
aonal athletes in general, but are even more important
in ambious, professional and top level sports. Gener-
ally, a conscious change in an athletes’ perspecve on
health has the potenal to iniate an advantageous par-
adigm shi in the behavior considering sports nutrion
and performance.
According to the ADA [174], “athlec performance
and recovery from exercise are enhanced by opmal
nutrion”, and thus “recommend appropriate selecon
of food and uids, ming of intake, and supplement
choices for opmal health and exercise performance.”
The American College of Sports Medicine (ACSM) [174]
and vegans, however, the daily intake was insucient in
three nutrients (calcium, zinc, vitamin B12) [192], with
vegans being decient in iodine instead of zinc [191].
Furthermore, it is known that vegans on average are
beer 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, bion 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 deciencies usually
emerge from poor applicaon, i.e. by misapplied dietary
behavior [86,133,134]. The nutrional adequacy of any
parcular kind of diet, including the vegan diet, depends
on personal nutrional 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 specic cases, sig-
nicant risks exist resulng 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 potenal deciencies can be easily avoided
[26], a vegan diet lacking any deciency can result from
careful planning, appropriate composion and prepara-
on, and with adequate supplementaon, when energy
needs are met [26,31,88]. However, with the threat of
dangerous half-knowledge is also persistent and oen
widespread, there is an obvious contradicon, because
sciencally proven reality is turned upside down when
discussions lack evidence and thus rate vegan diets as
eg. unhealthy, which seems inappropriate considering
the substanal 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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populaons, too.
In addion, 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 oen because it is good for main-
taining health (95%, p = 0.05), choosing it more oen
to obtain specic ingredients, eg. phytochemicals (59%,
p = 0.007), and even to avoid specic 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 benecially to their overall state of health, mainly
because they reported to be extraordinarily health-con-
scious, in parcular due to their food choice behavior.
In line with a recent study performed on ambious rec-
reaonal runners in the laboratory [196,199,200], these
ndings support the noon that adhering to a vegan di-
etary paern is compable with ambious 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 possibilies to further develop or completely
tap their athlec potenal. 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,
beneng post-exercise recovery and regeneraon,
and to enhance total performance capacity [201].
From the authors´ experience, not only among the
normal populaon but also frequently with athletes and
their coaches, nutrional knowledge is oen 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 oen in-
ict harm on themselves through detrimental nutrion
and suspect fueling pracces, rather than nourishment
for beer tness and peak performance [2] (p. 436).
Characteriscs of whole food vegan diets that aid
athlec performance
Based on the characteriscs 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 fay
acids) and thus low-calorie, and zero cholesterol nature
of vegan diets is especially characterisc. 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 (respecve-
ly rich in ber, phytochemicals and vitamins). The high
highlights in their current joint posion statement, that
“the performance of, and recovery from, sporng acv-
ies are enhanced by well-chosen nutrion strategies”.
Therefore, they provide nutrion guidelines to support
opmal health and athlec performance, spanning from
training to racing.
Even aer decades of research focussing on the ef-
fects of vegetarian diets on health, knowledge is sparse
about if and how veganism aects athlec performance.
Despite the abundance of evidence on the health ben-
ets that emerge from parcularly vegan diets [88],
whether a vegan diet per se promotes athlec (peak)
performance or not is sll unclear and remains to be de-
termined [11,12,101,196].
There is ample evidence from laboratory and eld
studies demonstrang that a well-planned vegetari-
an and vegan diet can meet the energy and nutrional
needs of compeve athletes [95]. Since well-planned
vegan diets are healthy and nutrionally adequate,
even for athletes, the ACSM [173] emphasizes that veg-
an diets can even meet the increased nutrional needs
of compeve athletes when energy requirements are
met, and when they contain high levels of vegetables
and fruits, nuts, whole grains, soy products, dietary ber,
anoxidants 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
eecve for endurance athletes (eg. runners, cyclists,
triathletes) [48], even though informaon about (strict)
vegetarian diets linked to athlec performance had
been sparse, if it existed at all. 32 years aer the inial
recommendaon, Austrian researchers documented for
the rst me the successful implementaon of vegan in-
race dietary taccs in ultra-endurance sports [20]. Aer
eight consecuve 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% beer than ex-
pected. Moreover, the vegan athlete was able to main-
tain an average speed of 15.6 km/h resulng from an ex-
ercise intensity of 88% of race induced maximum heart
rate (80% of laboratory determined maximum) over the
full stage race, with respecvely 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 eects of long-term or even lifeme
adherence to veganism in athlec performance is sll
limited to only two case studies performed on vegan ul-
tra-endurance athletes. Together, these data show that
vegan athletes are not only compeve (physiological
prole, race results), but further match the exercise-in-
duced nutrional demands of prolonged high intensity
training and racing [20,198]. These results suggest that a
carefully planned vegan diet diligently put into pracce
can be eecve for other athletes and specic athlec
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animal foods. This is due to much lower contaminaon
by health threatening noxious and toxic substances as
well as their residues resulng from absorpon (rao of
1:9 from drugs, toxins and heavy metals, along with a
rao up to 1:14 from pescides) [154-156,165].
The strong alkalizing nature of vegan diets
might not only have a posive 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-acve vegans show beer metabolic
parameters than non-vegans [209], vegan athletes will
benet even more from this opmal baseline metabol-
ic status, prior to any single unit of training or racing.
As a basis for performance, they lack other negave 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
promong diet, an alkaline promong diet with a mark-
edly low acid load was shown to increase anaerobic ex-
ercise me to exhauson during high intensity treadmill
running by +21%. This was calculated to translate to a
10-mes higher reducon 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 buer capacity (base excess, bicarbon-
ate concentraon), although anaerobic performance
was unaected [210], which may in part be due to the
dierent diets pre-exercise metabolic state [18,211].
Moreover, the posive relaonship between intake
of specic nutrients (eg. macronutrients such as com-
plex carbohydrates; micronutrients such as zinc; anoxi-
dants like vitamins C and E, polyphenols, beta-carotene)
and vegetarian kinds of diet with immune funcon is ev-
ident. Nutrional modulaon can play a role in mediat-
ing immunological eects with the opmum diet to best
support immune defense to prevent chronic inamma-
on and infecons [17,18,137]. Together, low-fat whole
food vegetarian diets, but especially vegan diets, ben-
ecially inuence inammaon, immune funcon and
anoxidant status by modulang the inammatory and
immune system (elevated biomarkers). Recent evidence
indicates such diets to improve (signicantly lower)
levels of serum C-reacve protein (CRP), brinogen, in-
terleukin-6, and total leukocyte concentraons, as well
as lymphocyte responsiveness and natural killer cell
funconality [17,18]. These advantageous but subtle
changes provide posive health outcomes and suggest
improvements that translate into benets for endur-
ance athletes that may result from an opmized intake
of phytochemicals (parcularly polyphenols) and unre-
ned carbohydrates, with low intakes of choline, beta-
ine, carnine and saturated fat at the same me [18].
Together, these facts are fundamentally advanta-
geous to vegan athletes, as they might posively aect
exercise performance during training and racing, and
likely constute a good prerequisite for sport and peak
ingeson of ber due to the high intakes of plant foods
results in rapid saety and thus decreased total energy
intake, which aids in the reducon of BW by reducing
of body fat mass [13,16]. Therefore, several indexes
that have evaluated overall nutrion relang to healthy
eang have rated vegan (vegetarian) diets as typically
beer (highest scores) than mixed diets (lowest scores)
[26,88,202], (p. 79).
The key benets to vegan athletes compared to
non-vegan foods and products are the higher intakes
of complex carbohydrates, dietary ber (only present
in plants), anoxidant 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, specic food items markedly aect the
metabolic regulaon of the organism by changes in the
acid-base balance with vegetables, fruits and potatoes
(low-PRAL food items) having the highest alkalizing po-
tenal [138,139,141,144,146]. While average values of
calculated dietary acid load for specic 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 excreon [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 dier (64.6
mEq) [142,145]. Thus, not suprisingly, a markedly dier-
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 excreon values found to
signicantly dier 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
capacies, buering enhanced accumulaon of blood
lactate and hydrogen ion levels reducing the pH-value).
Resulng from the digeson and the break-down of
foods and nutrients from animal sources, the organism
has to compensate for harmful substances in addion
to catabolic products (e.g. nitrogen, sulfur-containing
substances) and low-grade metabolic acidosis resulng
from higher dietary acid load [146], which together pose
another heavy burden on the exercise-induced metab-
olism. In addion, 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
intensies > 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 opmum 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 addion to endurance sports, they conrmed the
importance of carbohydrates to other types of athletes
such as rugby-players [228-230].
Sport and exercise cause changes in macronutrient
distribuons 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
rao 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
proporons 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 reected on the plate when planning an athlete´s
diet, and when composing and preparing meals [2] (p.
432). Therefore, a minimal carbohydrate to protein rao
[231] of at least 4:1 is advised for meal composion [2]
(p. 405). Drawn from the data of individual intakes pre-
sented in Table 3B, the carbohydrate to protein rao of
5:1 in vegans nicely matches this recommendaon and
provides opmal condions for promong an athlete’s
long-term health and exercise performance, while the
omnivores’ rao of 3:1 seems insucient. Moreover,
the rao of ≥ 8:1 in non-athletes is suggested to benet
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 constute 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 opmal eects in order to develop an ath-
lete’s overall potenal 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 funcons of the
human organism, including respiraon, circulaon,
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-
ung to daily calories reecng a convenonal dietary
paern [176,212-214] are presented in Table 3A. In ad-
dion, Table 3B presents the macronutrient distribuon
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 contribuon of only 40-45%
of total energy intake found in many Western civiliza-
ons [215] (p. 181).
Considering dietary recommendaons for the
non-acve general populaon, a recent study on recre-
aonal runners found that carbohydrate intake of omni-
vores (46.7%) is lower than recommended (> 50%) and
signicantly diers 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-
reaonal 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 sll
are today, usually neglected, while protein is overrated
[2] (pp. 397,402). It is evident that carbohydrates are
ulized by the body most eciently and thus constute
not only the preferred fuel at rest. Typically, complex
carbohydrates contribute the majority of a vegan’s en-
ergy intake. Non-acve vegans not only match the mac-
ronutrient guidelines but also meet the even higher
recommendaons for athletes as well as their in-race
energy needs (Table 3 and Figure 1).
By the early 1980s vegetarian dietary paerns were
already being recommended as parcularly eecve for
meeng high energy and carbohydrate demands [48],
especially for endurance athletes [47,183]. This is due
to the carbohydrate-rich characterisc of plant foods,
and since vegetarian diets can help endurance athletes
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quadriceps) were observed [178]. Independent of di-
etary paern, 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
recommendaons. However, the distribuon 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 adapve
response to training [240]. Independent of the habitual
dietary roune of recreaonal athletes (vegetarians or
vegans (n=18) vs. omnivores), creane supplementaon
during an 8-week resistance exercise training increased
intramuscular IGF-I concentraon [239]. In addion,
for an increase of 10 g/day of vegetable protein, but
not animal protein, a signicant increase in distance
walked was recently found (+20 m in a 6 min walking
test), suggesng plant protein to benecially aect ex-
ercise performance in non-acve subjects [241]. More-
over, oat protein was found to be protecve considering
the negave eects of eccentric exercise, parcularly
against muscle damage induced by downhill running, as
it markedly diminishes muscle soreness, reduces mark-
ers for muscle damage (serum creane kinase, myoglo-
bin) and inammaon (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 funconal capac-
the nutrional foundaon of health, but are also of even
more signicance to successful athletes, since carbohy-
drates are key at high metabolic rates and promotes
exercise performance. Resulng 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 nutrion recommendaons [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: Unl today, protein has been overrated
in general, and by men and athletes especially, with the
majority scking to the erroneous assumpon that ‘man
requires meat’. Mainly power and strength athletes sup-
port and pracce 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 potenal
and vigor, therefore athletes in parcular are always
concerned about geng 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-compable – muscles to success-
fully parcipate 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 dierences 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].
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since current research is generally lacking regarding the
impact on athlec 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
indicang that muscle mass and strength matches the
performance of omnivorous counterparts [20,198] as
well as muscle health of non-acve people [178]. There-
fore, undesired facts that might be due to eg. misin-
formaon, inadequateness or failure in sports-specic
dietary or training strategy can result in dramac disad-
vantages to an athlete´s health and sports performance,
but cannot be aributed to the vegan diet per se.
Yet, the most frequently asked queson addressed
to vegan athletes is sll loaded with severe doubt, and is
namely: ´How do you meet your protein needs?´ The In-
ternaonal Society of Sports Nutrion (ISSN) [249] con-
cluded in their posion 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
opmizing recovery and/or training adaptaons.
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 situaons such as starvaon or
extreme BW loss due to dietary intervenons, 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 quanty 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-acve 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 variaons
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-
tenally 10% lower protein digesbility 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 digesbility, 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 aforemenoned low-
er digesbility of plant proteins, a higher protein intake
that equals the respecve value of 1.3-1.8 g/kg*day of
BW is recommended for vegan athletes [174].
Although not all authories support higher pro-
tein intakes for athletes [174,175], some organizaons
ity [172,243]. Independent of kind of diet, total muscle
mass (including circumference of a specic muscle) can
be adapted by concrete intervenons that are decisive
to build muscle mass, eg. the appropriate training sm-
ulus as one crucial factor.
Not meeng the key requirements of adequate (1)
Energy intake, (2) Protein/amino acids intake, consider-
ing the amount and ming along with sucient 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
negave eect on health, and (iii) A negave impact on
athlec performance [20,170,173,174,231,244], [2] (p.
405), [84] (pp. 55-78), [232] (pp. 83-113). These aspects
inuence an athlete´s potenal to build and maintain
muscles that are compable to high-intensity and/or
long-term power and strength sports as well as endur-
ance sports, too.
Although, muscle mass alone as a predicve param-
eter to performance is not meaningful for rang the ap-
propriateness of specic kinds of diet in sports. To win
or lose depends on various performance-determining
factors within a specic prole of skills and capacies,
and is rather more complex than being limited to mus-
cle mass and/or strength. An athlete’s opmal physique
is related to factors such as age, sex and genecs [172-
174,243], and is linked to the specic demands of a giv-
en kind of sports or discipline.
However, among athletes, muscle mass is oen be-
lieved as the ulmate 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 negavely aect
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 parc-
ipaon in Olympic Games and World Championships).
From the experience of mentoring and supervising
ambious (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
addion, with the growing scienc interest especially in
vegan diets, there is special concern of the hypertrophic
potenal 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 unsubstanated. 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 sll remains to be proven. To date, no single
study has shown limitaons 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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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 benets emerging from a vegan diet (carbohydrate,
iron, ber) excel over omnivores and vegetarians for
recreaonal 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].
Resulng from this, a well-planned and supplement-
ed, and diligently implemented vegan diet is compable
with compeve sport and promotes a good state of
health with no risk of developing nutrional decien-
cies [10,11,13,26,196,199,200,254], [254] (p.778, 788).
However, because non-acve vegans have to supple-
ment vitamin B12, it is necessary for vegan athletes, too.
Despite there being no need for any other supplemen-
taon when vegan diets are based on a big variety of
wholesome plant foods [2] (pp. 431-432), supplements
might add benets as part of an athletes’ dietary strat-
egy.
However, due to the greatly increased metabolic rate
from me to me, well-trained (compeve) athletes
generally show a markedly higher need for energy, all
nutrients, vitamins and minerals, as well for as other vi-
tal substances. As the respecve 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
implementaon of their personalized exercise-induced
diet into daily scenarios is essenal for coping with the
higher nutrional requirements. This is necessary in
order to avoid exercise and diet-related under-supply,
which would result in imbalances and/or deciencies
with negave eects on both health and sports perfor-
mance [10