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Critical Reviews in Food Science and Nutrition
ISSN: 1040-8398 (Print) 1549-7852 (Online) Journal homepage: https://www.tandfonline.com/loi/bfsn20
Should dietary guidelines recommend low red
meat intake?
Frédéric Leroy & Nathan Cofnas
To cite this article: Frédéric Leroy & Nathan Cofnas (2019): Should dietary guidelines
recommend low red meat intake?, Critical Reviews in Food Science and Nutrition, DOI:
10.1080/10408398.2019.1657063
To link to this article: https://doi.org/10.1080/10408398.2019.1657063
© 2019 The Author(s). Published with
license by Taylor & Francis Group, LLC.
Published online: 05 Sep 2019.
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REVIEW
Should dietary guidelines recommend low red meat intake?
Fr
ed
eric Leroy
a
and Nathan Cofnas
b
a
Research Group of Industrial Microbiology and Food Biotechnology (IMDO), Faculty of Sciences and Bioengineering Sciences, Vrije
Universiteit Brussel, Pleinlaan 2, Brussels, B-1050, Belgium;
b
Balliol College, University of Oxford, Oxford, OX1 3BJ, UK
ABSTRACT
Mainstream dietary recommendations now commonly advise people to minimize the intake of red
meat for health and environmental reasons. Most recently, a major report issued by the EAT-
Lancet Commission recommended a planetary reference diet mostly based on plants and with no
or very low (14 g/d) consumption of red meat. We argue that claims about the health dangers of
red meat are not only improbable in the light of our evolutionary history, they are far from being
supported by robust scientific evidence.
KEYWORDS
red meat; health;
vegetarianism; veganism;
dietary guidelines; disease
1. Introduction
On January 16
th
, 2019, the EAT-Lancet Commission for-
mally expressed its desire for a Great Food Transformation
toward a predominantly plant-based diet for the planet
(Willett et al., 2019). The proposed reference diet includes
minute daily doses of beef (7 g), pork (7 g), and eggs (13 g),
with somewhat larger amounts of poultry (29 g) and fish
(28 g). Despite heavy restrictions on other animal source
foods, it allows for 250 g of dairy products per day, with a
limit of 153 kcal. Stricter vegetarian and even vegan diets
were sanctioned as valid options too, provided that vitamin
B12 supplements are taken in the case of veganism. In the
words of the Commission: “This healthy reference diet
…includes a low to moderate amount of seafood and
poultry, and includes no or a low quantity of red meat,
processed meat”(Willett et al., 2019). One of the “key
messages”is that “Healthy diets …consist of a diversity of
plant-based foods, low amounts of animal source foods.”
Red meat is specifically labeled as an “unhealthy food”.
While the authors acknowledge that livestock products can
offer benefits for those who are nutritionally deficient, a
strong reduction of animal products was said to be benefi-
cial for both health and the environment. Soon after the
release of this EAT-Lancet report, a similar argument was
made by yet another Lancet Commission, classifying meat as
a driver of the Global Syndemic—a system of interconnected
global crises related to health and the environment—and
arguing for an interventionist approach through mass-mar-
keting campaigns and legal measures, including the manda-
tory use of warning labels and the application of taxes
(Swinburn et al., 2019). Previously, other groups associated
with the EAT-Lancet Commission have made similar recom-
mendations. A study whose first author belongs to the EAT-
Lancet Commission recently called for taxes on meat
consumption (Springmann et al., 2018). The World
Research Institute, a direct partner of the EAT-Lancet net-
work, considers various interventions to reduce meat eating
with varying degrees of compulsion (e.g., influencing nutri-
tional labeling and dietary guidelines, stimulating 30-day
diet challenges, imposing taxes, and banning meat from
menus) (Ranganathan et al., 2016).
Contemporary arguments against meat eating appeal
mostly to nutritional, environmental, and ethical considera-
tions (Leroy, 2019). The present review focuses on nutrition.
Although the environmental and ethical arguments should
certainly not be overlooked, these require separate analyses.
Furthermore, the nutritional debate has its own complexities
and controversies, for instance with respect to the potential
health implications of shifts in macronutrient ratios toward
elevated levels of carbohydrates (e.g., Deghan et al., 2017)or
the reliance on ample amounts of cereals (e.g., Antvorskov
et al., 2018), soy (e.g., Siepmann et al., 2011), and plant oils
(e.g., DiNicolantonio, 2014). The present overview, therefore,
will be dedicated to the specific topic of severe meat restric-
tion or avoidance and the potential impact of such dietary
restriction on health. Ultimately, the conclusions will have
to be integrated into a more holistic evaluation that balances
nutrition, sustainability, and ethics.
2. Meat and health: a shifting paradigm?
Humans are biologically adapted to a diet that includes
meat. Archeological findings suggest that hominins were
butchering animals with stone tools 2.5 million years ago
(de Heinzelin et al., 1999). At some point we lost the ability
to absorb vitamin B12 in the large intestine, where it is pro-
duced by gut bacteria, making man dependent on dietary
sources of the vitamin (Schjønsby, 1989). Presumably our
ancestors were able to survive losing this ability because
CONTACT Nathan Cofnas nathan.cofnas@balliol.ox.ac.uk Balliol College, University of Oxford, Oxford, UK.
ß2019 The Author(s). Published with license by Taylor & Francis Group, LLC
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
CRITICAL REVIEWS IN FOOD SCIENCE AND NUTRITION
https://doi.org/10.1080/10408398.2019.1657063
they were regularly consuming B12-rich meat (Lents, 2018).
Hominin skeletal remains from 1.5 million years ago show
signs of porotic hyperostosis, which is generally linked to
B12 deficiency and is virtually absent in chimpanzees who
still obtain B12 from gut bacteria (Dom
ınguez-Rodrigo
et al., 2012). This provides some evidence that “by at least
the early Pleistocene meat had become so essential to proper
hominin functioning that its paucity or lack led to deleteri-
ous pathological conditions”(Dom
ınguez-Rodrigo et al.,
2012). Over time our capacity to convert the omega-3 fatty
acid alpha-linolenic acid (ALA), found in plants, to the bio-
logically important eicosapentaenoic acid (EPA) and docosa-
hexaenoic acid (DHA) forms (found primarily in seafood,
but also in meat, eggs, and dairy; Tur et al., 2012) became
greatly reduced in comparison to other primates (Stark
et al., 2016). The shift to energy-dense meat caused our
guts, particularly our large intestines, to shrink significantly
compared to those of apes. Gut proportions in humans are
also adapted to meat eating. Our small intestine (in which
most nutrients are extracted) comprises 56% of total gut vol-
ume, while the large intestine comprises about 20%—these
proportions are reversed in apes (Milton, 2003). Meat eating,
and the concomitant reduction in size of the energy-con-
suming gut, is believed to have played an essential role in
the increase of brain size in the hominin lineage. Because
the brain and gut compete for energy, the former was able
to increase in size when the latter became smaller (Aiello &
Wheeler, 1995). Gupta (2016) expounds: “To build and
maintain a more complex brain, our ancestors used ingre-
dients found primarily in meat, including iron, zinc, vitamin
B12 and fatty acids. Although plants contain many of the
same nutrients, they occur in lower quantities and often in a
form that humans cannot readily use.”
The fact that we are biologically adapted to diets that
include substantial amounts of meat does not by itself prove
that low-meat diets cannot be healthy. However, when it
comes to virtually every other species, we generally take it for
granted that it will flourish best on a diet that roughly resem-
bles the one to which it was adapted. It would be, though not
impossible, somewhat surprising if Homo sapiens turned out
to be such a spectacular exception to this principle.
Nevertheless, mainstream nutrition discourse often portrays
meat as a health disaster (see Leroy, 2019), suggesting that it
can be readily replaced with legumes and B12 supplements,
and whereby additional confusion is generated by sensational-
ist misrepresentations of the scientific evidence in mass media
(Leroy et al., 2018a). Nonetheless, the anti-meat discourse is
able to refer to a large set of international and peer-reviewed
scientific data that have been institutionalized in dietary
advice from various health authorities worldwide (e.g., WHO,
2015; NHS, 2018). These data are, for the largest part, gener-
ated from observational studies within the domain of nutri-
tional epidemiology, the limitations of which will be discussed
below. Taken together, it is repeatedly stated in academic lit-
erature that high meat intake is associated with higher mortal-
ity (Sinha et al., 2009; Pan et al., 2012; Larsson & Orsini, 2014;
Etemadi et al., 2017), cardiometabolic illnesses (Pan et al.,
2011; Chen et al., 2013; Feskens et al., 2013; Abete et al., 2014;
Yang et al., 2016; Kim & Je, 2018), diverse types of cancer
(Huang et al., 2013; Farvid et al., 2015; Carr et al., 2016), and
intestinal disorders (Cao et al., 2018). The above-mentioned
Lancet reports (Swinburn et al., 2019; Willett et al., 2019)
make recommendations based on this research, assuming
causal relationships between meat intake and morbidity
and mortality.
3. Meat eating and chronic disease: evaluation of
the evidence
3.1. Evidence from observational studies needs to be
interpreted with care
Despite the merits of epidemiology as a scientific discipline,
an overwhelming corpus of often non-robust and overstated
observational findings has been amassing over the last deca-
des in the field of nutrition (Ioannidis, 2018). Naïve inter-
pretations of these findings are often promoted by the
media and influence nutritional guidelines. Ioannidis illus-
trates the absurdity of taking them at face value:
Assuming the meta-analyzed evidence from cohort studies
represents life span-long causal associations, for a baseline life
expectancy of 80 years, eating 12 hazelnuts daily (1 oz) would
prolong life by 12 years (i.e., 1 year per hazelnut), drinking 3
cups of coffee daily would achieve a similar gain of 12 extra
years, and eating a single mandarin orange daily (80 g) would
add 5 years of life. Conversely, consuming 1 egg daily would
reduce life expectancy by 6 years, and eating 2 slices of bacon
(30 g) daily would shorten life by a decade, an effect worse than
smoking. (Ioannidis, 2018)
Schoenfeld and Ioannidis (2013) found that, among 50 com-
mon ingredients used in a cookbook, 40 had been associated
with cancer risk or benefit based on observational studies.
As a first point of concern, the input data obtained from
food frequency questionnaires should be interpreted pru-
dently as they can be problematic for a variety of reasons
(Schatzkin et al., 2003; Archer et al., 2018; Feinman, 2018).
Social desirability bias in food reporting is just one example,
as reported consumption can be affected by the perceived
health status of certain foods. Not all self-defined vegetarians
avoid meat, which is suggestive of a considerable risk for
underreported intake in health-conscious groups (Haddad &
Tanzman, 2003).
Secondly, diets are difficult to disentangle from other life-
style factors. It has been shown that Western-style meat eat-
ing is closely associated with nutrient-poor diets, obesity,
smoking, and limited physical activity (Alexander et al.,
2015; Fogelholm et al., 2015; Grosso et al., 2017; Turner &
Lloyd, 2017). Given the fact that health authorities have
been intensely promoting the view that meat is unhealthy,
health-conscious people may be inclined to reduce intake.
Typically, the associations between meat eating and disease
tend to be higher in North American than in European or
Asian cohort studies, indicating the presence of lifestyle bias
and the need for cross-cultural assessments (Wang et al.,
2016; Grosso et al., 2017; Hur et al., 2018). A pooled ana-
lysis of prospective cohort studies in Asian countries even
indicated that red meat intake was associated with lower
2 F. LEROY AND N. COFNAS
cardiovascular mortality in men and cancer mortality in
women (Lee et al., 2013). Likewise, when omitting Seventh-
Day Adventist studies from meta-analyses, the beneficial
associations with cardiovascular health for vegetarian diets
are either less pronounced or absent indicating the specific
effects of health-conscious lifestyle rather than low meat
consumption as such (Kwok et al., 2014; FCN, 2018). This is
important, as Seventh-Day Adventism has had considerable
influence on dietary advice worldwide (Banta et al., 2018).
As a third point, the relative risks (RRs) obtained from
observational studies are generally low, i.e., much below 2.
In view of the profusion of false-positive findings and the
large uncertainty and bias in the data due to the problems
mentioned above (Boffetta et al., 2008; Young & Karr,
2011), such low RR levels in isolation would not be treated
as strong evidence in most epidemiological research outside
nutrition (Shapiro, 2004; Klurfeld, 2015). Relationships with
RRs below 2, which are susceptible to confounding, can be
indicative but should always be validated by other means,
such as randomized controlled trials (RCTs) (Gerstein et al.,
2019). The association between meat eating and colorectal
cancer, for instance, leads to an RR estimate below 1.2,
whereas for the association between visceral fat and colorec-
tal neoplasia this value equals 5.9 (Yamamoto et al., 2010).
The latter provides a robust case that is much more deserv-
ing of priority treatment in health policy development.
To sum up, the case propagated by the EAT-Lancet
Commission (Willett et al., 2019) has essentially been based
on observational studies with RRs much below 2 (e.g., Sinha
et al., 2009; Pan et al., 2011,2012; Chen et al., 2013; Feskens
et al., 2013; Lee et al., 2013; Abete et al., 2014; Farvid et al.,
2015; Etemadi et al., 2017). We find this particularly prob-
lematic, as it is not good practice to infer a causal connec-
tion to meat eating from such weak and confounded
associational data (McAfee et al., 2010; Alexander et al.,
2015; Klurfeld, 2015; Feinman, 2018; Leroy et al., 2018b).
Moreover, the science used to incorporate the data from
meat studies into dietary policy making is all-too often par-
tial and inaccurate (Truswell, 2009). This concern is under-
lined by the fact that claims from observational
epidemiology very often fail to hold up when tested in
RCTs (Young & Karr, 2011). Nutritional epidemiology is a
useful tool for the generation of hypotheses, but its findings
as such do not provide a robust basis for the implementa-
tion of health policies in the absence of further substanti-
ation. Or, as stated by Gerstein et al. (2019), “analyses of
most observational data from the real world, regardless of
their sophistication, can only be viewed as hypothesis gener-
ating”. This is especially so when the results are counterin-
tuitive, as is the case for meat eating given its long record as
an essential food within our species-adapted diet.
3.2. Intervention studies have not been able to indicate
unambiguous detrimental effects
As stated by Abete et al. (2014), epidemiological findings on
meat eating “should be interpreted with caution due to the
high heterogeneity observed in most of the analyses as well
as the possibility of residual confounding”. The interactions
between meat, overall diet, human physiology (including the
gut microbiome), and health outcomes are highly intricate.
Within this web of complexity, and in contrast to what is
commonly stated in the public domain (Leroy et al., 2018a),
the current epidemiological and mechanistic data have not
been able to demonstrate a consistent causal link between
red meat intake and chronic diseases, such as colorectal can-
cer (Oostindjer et al., 2014; Turner & Lloyd, 2017).
RCTs can play an important role in establishing causal
relationships, and generally provide much stronger evidence
than that provided by observational data. However, even
RCTs are not fail-safe and can also be prone to a range of
serious flaws (Krauss, 2018). Intervention studies that over-
look the normal dietary context or use non-robust bio-
markers should be interpreted with caution, and do not
justify claims that there is a clear link between meat and
negative health outcomes (see Turner & Lloyd, 2017; Kruger
& Zhou, 2018). The available evidence generally suggests
that interventions with red meat do not lead to an elevation
of in vivo oxidative stress and inflammation, which are usu-
ally cited as being part of the underlying mechanisms trig-
gering chronic diseases (Mann et al., 1997; Hodgson et al.,
2007; Turner et al., 2017). Even in an epidemiological cohort
study that was suggestive of an inflammatory response based
on an increased CRP level, this effect became non-significant
upon adjustment for obesity (Montonen et al., 2013).
Moreover, a meta-analysis of RCTs has shown that meat
eating does not lead to deterioration of cardiovascular risk
markers (O’Connor et al., 2017). The highest category of
meat eating even paralleled a potentially beneficial increase
in HDL-C level. Whereas plant-based diets indeed seem to
lower total cholesterol and LDL-C in intervention studies,
they also increase triglyceride levels and decrease HDL-C
(Yokoyama et al., 2017), which are now often regarded as
superior markers of cardiovascular risk (Jeppesen
et al., 2001).
Based on the above, we conclude that there is a lack of
robust evidence to confirm an unambiguous mechanistic
link between meat eating as part of a healthy diet and the
development of Western diseases. It is paramount that the
available evidence is graded prior to developing policies and
guidelines, making use of quality systems such as GRADE
(Grading of Recommendations Assessment, Development
and Evaluation; Guyatt et al., 2008). One of the founders of
the GRADE system has issued a public warning that the sci-
entific case against red meat by the IARC panel of the
WHO has been overstated, doing “the public a disservice”
(Guyatt, 2015). The IARC’s(2015) claim that red meat is
“probably carcinogenic”has never been substantiated. In
fact, a risk assessment by Kruger and Zhou (2018) con-
cluded that this is not the case. Such hazard classification
systems have been heavily criticized, even by one of the
members of the IARC working group on red meat and can-
cer (Klurfeld, 2018). They are accused of being outmoded
and leading to avoidable health scares, public funding of
unnecessary research and nutritional programs, loss of
CRITICAL REVIEWS IN FOOD SCIENCE AND NUTRITION 3
beneficial foods, and potentially increased health costs
(Boyle et al., 2008; Anonymous, 2016; Boobis et al., 2016).
3.3. A scientific assessment should not overlook
conflicting data
Dietary advice that identifies meat as an intrinsic cause of
chronic diseases often seems to suffer from cherry-picking
(Feinman, 2018). One example of a fact that is typically
ignored is that hunter-gatherers are mostly free of cardiome-
tabolic disease although animal products provide the domin-
ant energy source (about two-thirds of caloric intake on
average, with some hunter-gatherers obtaining more than
85% of their calories from animal products; Cordain et al.,
2000,2002). In comparison, contemporary Americans obtain
only about 30% of calories from animal foods
(Rehkamp, 2016).
Whereas per capita consumption of meat has been drop-
ping over the last decades in the US, cardiometabolic dis-
eases such as type-2 diabetes have been rapidly increasing.
Although this observation does not resolve the question of
causality one way or the other, it should generate some
skepticism that meat is the culprit (Feinman, 2018).
Moreover, several studies have found either that meat intake
has no association with mortality/morbidity, or that meat
restriction is association with various negative health out-
comes (e.g., Key et al., 2009; Burkert et al., 2014; Kwok
et al., 2014; Lippi et al., 2015; Hur et al., 2018; Iguacel et al.,
2018; Yen et al., 2018). As another example of conflicting
information, the epidemiological association pointing to a
potential role of the meat nutrient L-carnitine in atheroscler-
osis via trimethylamine N-oxide (TMAO) formation (Koeth
et al., 2013), is contradicted by intervention studies
(Samulak et al., 2019) and epidemiological data showing
that fish intake, being by orders of magnitude the largest
supplier of TMAO (Zhang et al., 1999), improves triglycer-
ides and HDL levels (Alhassan et al., 2017).
Although all of the aforementioned studies—particularly
the observational ones—clearly have their limitations, they
equally deserve to be incorporated in the scientific analysis
and health debates.
4. The nutritional benefits of meat
Throughout human history, meat has delivered a wide range
of valuable nutrients that are not always easily obtained (or
obtainable) from plant materials (Williams, 2007; McAfee
et al., 2010; Pereira & Vicente, 2013; Young et al., 2013;
McNeill, 2014; Leroy et al., 2018b). A major asset of meat is
of course its high protein value (Burd et al., 2019), with
especially lysine, threonine, and methionine being in short
supply in plant-derived diets. It brings in B vitamins (with
vitamin B12 being restricted to animal sources only), vita-
mins A, D, and K2 (particularly via organ meats), and vari-
ous minerals with iron, zinc, and selenium being of
particular importance. Also, the long-chain omega-3 fatty
acids EPA and DHA present in animal sources are only
poorly obtained in vivo from a-linolenic acid conversion
(Cholewski et al., 2018), making plants a suboptimal source.
Despite being overlooked in most nutritional evaluations,
meat also contains various bioactive components as taurine
(Laidlaw et al., 1988), creatine (Rae et al., 2003; Benton &
Donohoe, 2011), carnosine (Everaert et al., 2011), as well as
conjugated linoleic acid, carnitine, choline, ubiquinone, and
glutathione (Williams, 2007). These components can offer
important nutritional benefits, for instance with respect to
the optimal development of cognitive functions.
Sufficient intake of animal products is therefore particu-
larly advisable for population groups with enhanced nutri-
tional needs and is helpful to offer nutritional robustness
during various stages of life. As such, it contributes to the
physical and cognitive development of infants and children
(Neumann et al., 2007; Hulett et al., 2014; Tang & Krebs,
2014; Cofnas, 2019) and prevents deficiencies in young
females (Fayet et al., 2014; Hall et al., 2017). In the elderly,
sufficient meat intake can prevent or improve malnutrition
and sarcopenia, also improving health-related quality of life
(Pannemans et al., 1998; Shibata, 2001; Phillips, 2012;
Rondanelli et al., 2015; Torres et al., 2017).
5. Meat avoidance leads to a loss of
nutritional robustness
Diets poor in animal source foods can lead to various nutri-
tional deficiencies, as already described more than a century
ago for the case of pellagra (Morabia, 2008), a condition
which remains relevant today for poorly planned vegan diets
(Ng & Neff, 2018). Advocates of vegetarian/vegan diets usu-
ally admit that these diets must indeed be “well-planned”in
order to be successful, which involves regular supplementa-
tion with nutrients such as B12. However, realistically, many
people are not diligent about supplementation, and will
often dip into deficient or borderline-deficient ranges if they
do not obtain nutrients from their regular diet. In such
cases, general malnutrition (Ingenbleek & McCully, 2012),
poorer health (Burkert et al., 2014), and nutrient limitations
(Kim et al., 2018) may be the result, as found in various
countries, such as Denmark (Kristensen et al., 2015),
Finland (Elorinne et al., 2016), Sweden (Larsson &
Johansson, 2002), and Switzerland (Sch€
upbach et al., 2017).
For example, a substantial number of vegetarians and vegans
are in the deficient or borderline-deficient range for B12
(Herrmann & Geisel, 2002; Herrmann et al., 2003), despite
the fact that the need for B12 supplementation is well-publi-
cized (see also Herbert, 1994; Hokin & Butler, 1999;
Donaldson, 2000; Elmadfa & Singer, 2009; Gilsing et al.,
2010; Obersby et al., 2013; Pawlak et al. 2013,2014; Pawlak,
2015; Woo et al., 2014; Naik et al., 2018). B12 deficiency is
particularly dangerous during pregnancy (Specker et al.,
1988,1990; Bjørke Monsen et al., 2001; Koebnick et al.,
2004), childhood (Rogers et al., 2003) and adolescence (van
Dusseldorp et al., 1999; Louwman et al., 2000).
Other potentially challenging micronutrients for people
on plant-based diets include (but are not limited to) iodine
(Krajcovicov
a-Kudl
ackov
a et al., 2008; Leung et al., 2011;
Brantsaeter et al., 2018), iron (Wilson & Ball, 1999;
4 F. LEROY AND N. COFNAS
Wongprachum et al., 2012; Awidi et al., 2018), selenium
(Schultz & Leklem, 1983; Kadrabov
a et al., 1995), and zinc
(Foster et al., 2013). Even if plant-based diets contain alpha
linolenic acid, this may not (as noted) prevent deficiencies
in the long-chain omega-3 fatty acids EPA and DHA (Rosell
et al., 2005), which can pose serious risks in pregnancy and
for growing children (Burdge et al., 2017; Cofnas, 2019).
Risks of nutritional deficiency are also documented by an
extensive list of clinical case reports in the medical literature,
with serious and sometimes irreversible pathological symp-
toms being reported for infants (e.g., Shinwell & Gorodisher,
1982; Zengin et al., 2009; Guez et al., 2012; Bravo et al.,
2014; Kocaoglu et al., 2014; Goraya et al., 2015), children
(e.g., Colev et al., 2004; Crawford & Say, 2013), adolescents
(e.g., Chiron et al., 2001; Licht et al., 2001;O’Gorman et al.,
2002), and adults (e.g., Milea et al., 2000; Brocadello et al.,
2007; De Rosa et al., 2012; Førland & Lindberg, 2015). The
latter reports commonly refer to failure to thrive, hyperpara-
thyroidism, macrocytic anemia, optic and other neuropa-
thies, lethargy, degeneration of the spinal cord, cerebral
atrophy, and other serious conditions. Although the direc-
tion of causality is not clear, meat avoidance is statistically
associated with eating disorders and depression (Zhang
et al., 2017; Barthels et al., 2018; Hibbeln et al., 2018; Matta
et al., 2018; Nezlek et al., 2018) and may mirror neurological
problems (Kapoor et al., 2017).
Our main concern is that avoiding or minimizing meat
consumption too strictly may compromise the delivery of
nutrients, especially in children and other vulnerable popula-
tions. Evidently, health effects of plant-based approaches
depend largely on the dietary composition (Satija et al.,
2016). Yet, the more restricted the diet and the younger the
age, the more this will be a point of attention (Van Winckel
et al., 2011). According to Cofnas (2019), however, even
realistic vegetarian diets that include diligent supplementa-
tion can put children at risk for deficiencies and thereby
compromise health in both the short and long term. There
is some direct and indirect evidence that the elevated phyto-
estrogen intake associated with low-meat diets may pose
risks for the development of the brain and reproductive sys-
tem (Cofnas, 2019). Moreover, attempts to introduce dietary
modifications that are also compatible with vegan philoso-
phy often pose a medicosocial challenge (Shinwell &
Gorodischer, 1982). In our opinion, the official endorsement
of diets that avoid animal products as healthy options is
posing a risk that policy makers should not be taking. As
stated by Giannini et al. (2006): “It is alarming in a devel-
oped country to find situations in which a child’s health is
put at risk by malnutrition, not through economic problems
but because of the ideological choices of the parents”.
6. Conclusions
Although meat has been a central component of the diet of
our lineage for millions of years, some nutrition author-
ities—who often have close connections to animal rights
activists or other forms of ideological vegetarianism, such as
Seventh-Day Adventism (Banta et al., 2018)—are promoting
the view that meat causes a host of health problems and has
no redeeming value. We contend that a large part of the
case against meat is based on cherry-picked evidence and
low-quality observational studies. The bald claim that red
meat is an “unhealthy food”(Willett et al., 2019) is wildly
unsupported.
Based on misrepresentations of the state of the science,
some organizations are attempting to influence policy mak-
ers to take action to reduce meat consumption.
Simplification of complex science increases persuasive power
but may also serve ideological purposes and lead to scientis-
tic approaches. According to Mayes and Thompson (2015),
manifestations of nutritional scientism in the context of bio-
politics can have various ethical implications for “individual
responsibility and freedom, concerning iatrogenic harm, and
for well-being”. Well-meaning yet overemphasized and pre-
mature recommendations may eventually cause more dam-
age than benefit, not only physiologically but also by
unjustifiably holding individuals accountable for their health
outcomes. We believe that a large reduction in meat con-
sumption, such as has been advocated by the EAT-Lancet
Commission (Willett et al., 2019), could produce serious
harm. Meat has long been, and continues to be, a primary
source of high-quality nutrition. The theory that it can be
replaced with legumes and supplements is mere speculation.
While diets high in meat have proved successful over the
long history of our species, the benefits of vegetarian diets
are far from being established, and its dangers have been
largely ignored by those who have endorsed it prematurely
on the basis of questionable evidence.
Acknowledgements
FL acknowledges financial support of the Research Council of the Vrije
Universiteit Brussel, including the SRP7 and IOF342 projects, and in
particular the Interdisciplinary Research Program ‘Tradition and natur-
alness of animal products within a societal context of change’(IRP11).
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