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Building a Stronger Vegan Movement Through Evidence-Based Communication
Note: This post is written in a personal capacity. The views expressed here are my own and do not represent those of any organisation I’m affiliated with. I'm grateful to Aaron Boddy, Elizabeth Crewe, Sebastian Joy, Aidan Kankyoku, Tobias Leenaert, Ginny Messina, and Felix Werdermann for their valuable input and feedback, which does not imply endorsement of the views presented.
In this post, I aim to show that messaging in the vegan movement often understates the challenges and uncertainties of vegan diets and does not fully reflect the available evidence from nutrition science. I make the case that a more evidence-based approach would strengthen the movement's long-term impact by better supporting people in navigating the existing challenges and uncertainties, and accelerating the systemic change and scientific progress needed to reduce them over time.
I have been part of the vegan movement for more than a decade and continue to be deeply committed to its goals. When I became vegan, it was purely for ethical reasons. Through my professional work as well as my activism, I repeatedly encountered questions about vegan nutrition that I did not feel well equipped to answer. As a result, I came to see learning more about nutrition science as a way to become a better vegan advocate. I have since spent years studying the field, and it has become one of my biggest passions. The more I learned, the more I began to question some of the ways nutrition science is communicated within the vegan movement, which ultimately led me to the perspective I present here.
The current narrative in the vegan movement tends to present vegan diets as easy to follow and healthy without much effort or notable risk.[1] This often involves suggesting that eating a varied diet and supplementing vitamin B12 is enough, without clearly communicating the importance of additional supplementation or attention to specific nutrients, while presenting the science around vegan diets as largely settled.
This framing may well lower the perceived barriers to adopting vegan diets. However, it understates the practical and nutritional challenges, as well as the remaining scientific uncertainties, and is not well-supported by the available evidence, which I discuss in the Nutrition Review.
While individual organisations and advocates differ in their messaging, the broader pattern is visible throughout the movement: across different philosophical orientations and strategic approaches, and in contexts ranging from personal outreach and public communication to institutional engagement. I assume only the best of intentions among everyone involved and am not looking to judge or blame anyone for decisions that were made in good faith.
I want to take a moment to appreciate where the current narrative about vegan diets comes from. Many vegan advocates are deeply motivated by compassion for animals and want to reduce their suffering as much as possible, recognising that animals have their own inner worlds and that their lives matter to them just as ours matter to us. This naturally creates an instinct to present vegan diets in the most appealing way possible. After all, anything that makes veganism seem challenging could discourage people from going vegan and therefore be counterproductive to the goal of helping animals.
The same motivation can also make it harder to find the truth. If we strongly believe that people should avoid animal products for ethical reasons and make this part of our identity, evidence suggesting that doing so could also have downsides can create cognitive dissonance. This can make us more susceptible to confirmation bias, where we give greater weight to evidence that supports what we already believe, and motivated reasoning, where we interpret evidence in ways that support our desired conclusions. As a result, we may for example be more likely to attribute findings that raise concerns about vegan diets to researcher bias or industry influence, while scrutinising favourable findings less critically. These dynamics can affect all of us, and recognising them can help us engage more openly with the evidence and develop a more accurate understanding of the challenges and uncertainties associated with vegan diets.
While the current narrative is motivated by a genuine desire to do good, it poses various strategic risks for the vegan movement:
More People Abandoning Vegan Diets: Understating the practical and nutritional challenges of vegan diets may create unrealistic expectations and inaccurate assumptions. This may leave people inadequately prepared to cope with and address these challenges, potentially resulting in poor health outcomes or disappointment and making them more likely to abandon the diet.[2]
Avoidable Harm to People: Health problems matter in their own right and can be particularly serious for vulnerable groups like children, pregnant people, and older adults.[3] Some nutritional deficiencies can stay hidden until their effects are difficult to reverse.[4] Taking this harm into account is especially relevant for a movement rooted in compassion and focused on reducing suffering.
A Weakened Case for Vegan Diets: Vegans with health problems contribute to negative perceptions of vegan diets and may not only quit the diet but also speak out against it.[5] As the vegan population grows, so will the number of unhealthy vegans and vocal ex-vegans. Poor health among vegans can also weaken the case for vegan diets when reflected in study results.[6]
Alienation of Potential Allies: Understating the challenges of vegan diets can create pressure for individual diet change, make vegan advocacy more confrontational, and fuel hostility towards ex-vegans.[7] Those who struggle with a vegan diet may feel discouraged or judged, potentially leading to defensiveness and disengagement from a movement they might otherwise support.
A Missed Opportunity to Improve Food Options: The vegan movement influences which plant-based options are available in retail and food service through industry engagement, political advocacy, and public messaging. If we fail to communicate where today’s options still fall short nutritionally, we reduce incentives to prioritise nutrition alongside price, taste, and convenience.[8]
Failure to Prepare for AI-Enabled Transparency: As AI becomes more capable and widely used, consumers gain easier access to nutritional information and expertise, which could give nutritional quality greater weight in consumer choices. If plant-based food options fail to meet expectations, consumers may increasingly reject them and lose trust in vegan diets more broadly.[9]
Taken together, these strategic risks reveal a fundamental trade-off: presenting vegan diets as already easy to follow and healthy without much effort or notable risk may encourage more people to adopt them in the short term, but it can also undermine the impact of the vegan movement in the long term, which depends not only on how many people adopt vegan diets, but also on how many sustain them, as well as on the overall reduction in animal product consumption. Notably, people for whom a vegan diet is not a sustainable choice could still substantially reduce their animal product consumption. This would increase demand for plant-based food options, which in turn would help change the food environment in ways that make it easier for others to reduce their animal product consumption, thereby creating a self-reinforcing dynamic. Overall, many people eating fewer animal products can have a bigger impact than fewer people giving up animal products entirely.
Addressing the strategic risks outlined above requires a more evidence-based narrative: one that retains the moral ambition at the heart of the vegan movement, while better supporting people in navigating the existing challenges and uncertainties of vegan diets today and accelerating the systemic and scientific progress needed to reduce them over time. I propose a narrative based on three guiding principles:
Realistic: Vegan diets are viable and can be healthy, but they are often more demanding in everyday life and require knowledge of how to obtain key nutrients, attention to food choices, and a commitment to supplementation. In addition, some uncertainties remain.[10]
In essence, the proposed narrative represents a strategic shift for the vegan movement: from optimising for short-term gains to optimising for long-term growth. Rather than trying to make vegan diets appear as appealing as possible, it focuses on actually making them as appealing as possible. The case studies in the Nutrition Review illustrate how this proposed narrative could translate into practice.
I understand the instinct to present vegan diets in the most appealing way possible, and I have often had it myself. The scale of suffering caused by animal agriculture is almost impossible to comprehend. However, I have come to believe that acting on this instinct does more harm than good. Looking at the bigger picture, vegans are still only a small minority despite decades of advocacy and substantial improvements in both the availability of plant-based food options and the social acceptance of veganism,[11] while global animal product consumption has continually risen.[12] This may point to underlying issues that existing strategies have overlooked. In light of this, I believe that the most promising path to meaningful and lasting change is to ensure that people who adopt vegan diets also thrive on them. This requires giving people the information they need to navigate the challenges and uncertainties that exist today, while gradually reducing them over time. Neither is possible without acknowledging that these challenges and uncertainties are real. But seeing the world as it is does not mean accepting it as it is. If anything, it should make us more determined to change it.
This review examines some of the nutritional claims underlying the current narrative and how well they are supported by the available evidence.
The following selection of case studies is not exhaustive and instead focuses on issues that are particularly relevant to public and scientific discourse around vegan diets. The aim is not to single out isolated inaccuracies, but to illustrate a broader pattern. Overall, the case studies highlight substantial nutritional challenges of vegan diets and show that vegans often fall short of the intakes recommended by nutrition authorities for several nutrients. Notably, these intake recommendations are primarily designed to prevent deficiencies, not to optimise health.[13] This means that intakes above these recommendations can in some cases provide meaningful benefits and contribute to a more positive experience with vegan diets.
In each case study, I present the current narrative as a synthesis of common claims across the movement, analyse the evidence, and propose an alternative narrative that better aligns with the evidence while also supporting the strategic shift outlined earlier. I then discuss the limits of epidemiological evidence on vegan diets and remaining uncertainties about their long-term health effects.
Current Narrative: Vegans can meet their protein requirements without difficulty by eating a varied diet, as protein deficiency is extremely rare in high-income countries. An intake of 0.8 g/kg of body weight per day is an appropriate target, while higher intakes are unnecessary and potentially even harmful.
Analysis: The 0.8 g/kg/day corresponds to the recommended dietary allowance (RDA) for healthy adults established by the U.S. Institute of Medicine.[14] The RDA for protein is based on nitrogen balance studies designed to estimate minimum adequate intake rather than optimal intake,[15] as explained by protein researcher Don Layman[16] or noted by Harvard Medical School[17]. While there is no consensus on the exact optimal intake, leading protein researchers suggest that 1.2–1.6 g/kg/day is a reasonable target, depending on factors such as age and activity level.[18] This may be particularly important for vegans due to the lower digestibility of plant proteins, with some recommendations suggesting ~20% higher intakes to compensate.[19] In practice, data from the EPIC-Oxford cohort show average protein intakes of 0.91–0.99 g/kg/day among vegans compared to 1.14–1.32 g/kg/day among omnivores, with 16.5% of vegan men and 8.1% of vegan women not even meeting the estimated average requirement (EAR) of 0.66 g/kg/day, which is the intake expected to meet the requirements of 50% of people.[20] Similarly, a systematic review found that 27–41% of vegans fall below the RDA, depending on the cohort.[21] In one recent randomised controlled trial, participants who were asked to follow a self-selected vegan diet saw their protein intake decline and after 12 weeks, lost more skeletal muscle mass and had lower rates of muscle protein synthesis than those who continued their habitual omnivorous diet.[22] Overall, while clinical protein deficiency is extremely rare in high-income countries, inadequate and suboptimal protein intake is considerably more common, especially among vegans.
Proposed Narrative: Protein requires particular attention on vegan diets. Plant-based alternatives and meals often provide less protein than the animal-based options they replace. Moreover, because plant proteins are generally less digestible, vegans may have higher protein requirements than omnivores and should ideally aim for around 1.2–1.6 g/kg/day. As a general rule, each meal should contain a substantial protein source, taking into account that legumes are not a one-to-one substitute for meat in terms of protein. Practical ways to increase protein intake include choosing meat alternatives with a high protein-to-calorie ratio, favouring soy or pea over oat milk, replacing conventional pasta with legume-based pasta, and using protein powder when needed. Producers and food service providers should ensure that plant-based products and meals provide meaningful amounts of protein, particularly where they replace animal-based equivalents.
Current Narrative: Vegans can meet their omega-3 requirements without difficulty by regularly eating plant sources such as walnuts, flax seeds, chia seeds, and hemp seeds.
Analysis: Omega-3 fatty acids occur in plants as alpha-linolenic acid (ALA), and in marine sources such as microalgae and fish as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). EPA and DHA are linked to many of the health benefits associated with omega-3 and are one of the main reasons health authorities recommend consuming oily fish. The body can convert ALA into EPA and DHA, but this conversion is limited.[23] Direct intake of EPA and DHA is therefore a much more reliable way to ensure an adequate supply, as explained by omega-3 researcher Bill Harris[24]. The European Food Safety Authority (EFSA) recommends an intake of 250 mg/day of combined EPA and DHA for healthy adults.[25] A systematic review found consistently lower EPA and DHA intakes among vegans than omnivores.[26] For example, data from the EPIC-Oxford cohort show average EPA and DHA intakes of 27 mg/day and 4 mg/day among vegans, compared with 94 mg/day and 172 mg/day among omnivores. Omega-3 intake does not necessarily reflect omega-3 status, so it is also useful to look at blood levels. The Omega-3 Index measures EPA and DHA levels in red blood cells, with levels below 4% considered high-risk and levels above 8% proposed as an optimal target.[27] Data from the Adventist Health Study 2 show an average Omega-3 Index of 3.7% among vegans, compared with 5.0% among omnivores and 5.7% among pescatarians.[28] Taken together, this suggests that relying on ALA from plant foods is unlikely to reliably achieve optimal omega-3 status.
Proposed Narrative: Many of the health benefits associated with omega-3 are linked specifically to EPA and DHA. Vegans should supplement EPA and DHA directly from microalgae rather than relying on the conversion of ALA alone. At the same time, plant-based products that are marketed or commonly expected to provide omega-3, such as plant-based fish alternatives, should provide meaningful amounts of EPA and DHA instead of using ALA as their primary omega-3 source.
Current Narrative: Vegans can meet their calcium requirements without difficulty by regularly eating plant sources such as dark leafy greens, legumes, nuts, seeds and their butters, particularly tahini, as well as calcium-fortified foods.
Analysis: Many plant foods contain meaningful amounts of calcium, but generally provide much less per serving than dairy products. In addition, calcium absorption can be substantially reduced by compounds such as oxalates and phytates. For example, sesame seeds are rich in calcium, but also high in oxalates, both of which are concentrated in the hull. As a result, neither light tahini (made from hulled seeds) nor dark tahini (made from unhulled seeds) provides much bioavailable calcium per calorie or in typical serving sizes. While calcium from low-oxalate vegetables such as broccoli and kale is highly bioavailable, relying on these foods as major calcium sources requires consuming relatively large quantities on a consistent basis. For healthy adults, EFSA recommends a calcium intake of 1000 mg/day for those aged 18–24 and 950 mg/day for those aged 25 and older.[29] A systematic review found lower calcium intake among vegans across numerous studies, with approximately 76% of vegans consuming less than the recommended intake.[30] Data from the EPIC-Oxford cohort show average calcium intakes of 839–862 mg/day among vegans compared to 1078–1120 mg/day among omnivores,[31] further indicating that inadequate calcium intake is common among vegans. Lower calcium intake may contribute to the significantly increased risk of fractures associated with vegan diets, alongside other factors such as lower protein intake.[32]
Proposed Narrative: Vegans need to take deliberate steps to ensure adequate calcium intake. In practice, this generally means either consuming substantial amounts of low-oxalate dark leafy greens on a daily basis, which can be difficult in the current food environment, or relying on a well-planned combination of fortified foods and supplements. Producers of plant-based alternatives to dairy products should ensure that these products are fortified with calcium, while restaurants, canteens, and other food service providers should ensure that low-oxalate dark leafy greens are a regular part of plant-based meal options.
Current Narrative: Vegans can meet their zinc requirements without difficulty by regularly eating plant sources such as legumes, whole grains, nuts, and seeds.
Analysis: Many plant foods contain meaningful amounts of zinc, but they are also often rich in phytate, which substantially reduces zinc absorption. Accordingly, zinc requirements depend strongly on phytate intake: for healthy adults, EFSA recommends an intake of 7.5 mg/day for women and 9.4 mg/day for men on low-phytate diets, and 12.7 mg/day for women and 16.3 mg/day for men on high-phytate diets. As vegan diets are typically high in phytates, the higher requirements generally apply. A systematic review found that while average zinc intake is similar across dietary patterns, lower zinc bioavailability in vegan diets means that requirements are often not met, with zinc deficiency found in 30% of vegans compared with 13% of omnivores.[33] For example, data from the EPIC-Oxford cohort show average zinc intakes of 9.4 mg/day for vegan men and 8.4 mg/day for vegan women, compared with 10.9 mg/day for omnivorous men and 10.4 mg/day for omnivorous women, with 73.6% of vegan men and 55.8% of vegan women having intakes below the bioavailability-adjusted EAR of 11.0 mg/day for men and 8.3 mg/day for women.[34] The EAT-Lancet Planetary Health Diet provides an interesting case in point. An analysis of its micronutrient adequacy found that zinc intake was insufficient once the lower zinc bioavailability resulting from its high phytate content was taken into account.[35] This shortfall is particularly notable given that the Planetary Health Diet was developed by an international commission of experts, illustrating the challenge of meeting zinc requirements even in a carefully designed plant-rich diet.
Proposed Narrative: Zinc requires particular attention on vegan diets because it is generally less abundant and its absorption is reduced by the high phytate content of many plant-foods. Vegans should aim for around 13 mg/day for women and 16 mg/day for men. Possible ways to increase zinc intake include choosing whole grains over refined grains, adding nuts or seeds to meals, and choosing zinc-fortified foods where available, while zinc absorption can be improved by soaking and sprouting beans and grains, or choosing yeast- or sourdough-leavened breads. Overall, however, supplementation provides a much more reliable way to ensure sufficient zinc intake. Plant-based food producers should also help address this challenge through appropriate zinc fortification that accounts for bioavailability.
Current Narrative: Appropriately planned vegan diets can safely provide adequate nutrition during pregnancy, as supported by the US Academy of Nutrition and Dietetics (AND), the world’s largest organisation of nutrition and dietetics practitioners.
Analysis: The widely cited statement by the AND that vegan diets are adequate during all stages of life, including pregnancy, comes from its 2016 position paper[36] that expired in 2021 and has since been replaced by a new position paper that no longer covers pregnancy. The authors also had various unreported potential ideological and financial conflicts of interest,[37] and importantly, the AND’s position does not reflect an international scientific consensus, with several nutrition authorities considering the available evidence insufficient to establish the suitability of vegan diets during pregnancy. For example, while the UK National Health Service (NHS) considers well-planned vegan diets capable of meeting nutritional needs during pregnancy,[38] the German Nutrition Society (DGE) does not recommend either for or against them and warns of increased risk of nutrient deficiencies with potentially irreversible consequences,[39] and the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) finds the evidence on vegan pregnancy outcomes too limited to assess.[40] A systematic review examining vegan pregnancies found lower intakes of protein and several critical micronutrients among vegan compared with omnivorous pregnant women and indications of lower birth weight among their children.[41] At the same time, only a few studies met the inclusion criteria, leading the authors to conclude that the evidence is insufficient to assess the effects of a vegan diet during pregnancy for both mother and child.
Proposed Narrative: Given the high stakes and remaining scientific uncertainty, vegan diets during pregnancy should be approached with a high degree of caution. There is no consensus among international nutrition authorities that vegan diets are nutritionally adequate during pregnancy, and inadequate nutrient intake may pose risks to both mother and child. Anyone following a vegan diet during pregnancy should carefully plan their diet and use appropriate supplementation in consultation with a qualified nutrition professional. More research is needed to confidently establish the safety of vegan diets during pregnancy.
Current Narrative: Concerns about ultra-processed foods are often overstated. What matters is the nutritional composition of a food, particularly its levels of fat, sugar, and salt, rather than its degree of processing. Additives used in ultra-processed foods undergo rigorous safety assessments and provide important benefits, such as improved food safety and longer shelf life.
Analysis: Processing can provide important nutritional benefits. In particular, plant-based meat alternatives can provide convenient sources of protein and, when appropriately fortified, nutrients that can be more challenging to obtain on vegan diets.[42] However, apart from high levels of fat, sugar, and salt, there are several other health concerns associated with processed foods.[43] These include overconsumption promoted by hyper-palatable formulations, changes to the food matrix that may affect digestion, nutrient absorption, and satiety, and potential harms linked to additives, for which safety assessments can change as new evidence emerges[44]. Another concern is limited transparency. Compared with whole foods, the quality of processed foods is more difficult to assess, as lower-quality ingredients can be masked with flavourings, sweeteners, or salt. In addition, labels rarely disclose ingredient proportions, micronutrient content, or the specific forms of nutrients. This is particularly relevant given the potentially diverging interests of producers and consumers. For example, oat milk producers often use enzymes to break down starches into sugars, allowing products to be labelled “no added sugar” despite containing significant amounts of maltose, which raises blood sugar more than twice as much as lactose from dairy. Labels on iron-fortified plant-based meat alternatives show the total iron content without indicating that it is non-heme iron, which is considerably less bioavailable than the heme iron found in meat.[45] Similarly, fish alternatives mostly use low-cost omega-3 sources such as ALA from rapeseed oil, without the product information distinguishing these from the more valuable EPA and DHA from marine sources. Such issues may contribute to a broader sense of scepticism towards ultra-processed foods and plant-based alternatives to animal products in particular.
Proposed Narrative: The degree of processing should not be treated as a reliable indicator of the healthfulness of individual foods. Ultra-processed foods can not only be part of a healthy diet but also play an important nutritional role, such as plant-based meat alternatives for meeting protein requirements on vegan diets. At the same time, concerns about their health effects should be taken seriously. Ultra-processed foods vary substantially in their nutritional quality, and limiting their consumption can be a reasonable heuristic when assessing individual products is impractical. Plant-based products should therefore be held to high standards of nutritional quality and transparency. Where they are marketed as substitutes for specific animal products, they should provide comparable levels of key nutrients. Shortcomings should be called out to create stronger incentives for product improvements.
At first glance, the nutritional challenges highlighted by the case studies may seem difficult to reconcile with many epidemiological findings suggesting that vegans have similar or better health outcomes than omnivores. However, there are several plausible explanations for this apparent discrepancy:
Confounding: Many of the health benefits associated with vegan diets may result from factors such as eating more whole plant foods and less processed meat rather than from eliminating animal products altogether. Vegans also tend to be more health-conscious than the general population and differ in socioeconomic and other factors that influence long-term health, which cannot be fully accounted for statistically.[46]
Dietary Misclassification: Diet is typically assessed only periodically during a study, making it difficult to account for dietary changes that happen in between. This matters particularly for vegan diets, as many people do not maintain them over the long term.[47] If participants are classified as vegans based on their diet at the beginning of a study, that classification becomes inaccurate if they later start eating animal products. Excluding these participants from the analysis avoids this problem, but can create selection bias if some of them stop being vegan because of adverse health effects. Reassessing diet at follow-ups can help, but participants who start eating animal products between assessments will be misclassified as vegans until the next follow-up.
Effects of Dietary History: Vegans may have eaten animal products for much of their lives, which is particularly relevant because nutrition during critical periods of development, especially pregnancy and early childhood, can substantially influence health later in life.[48] Adult vegans who consumed animal products during these periods therefore cannot provide evidence about the health effects of vegan diets followed from birth or over multiple generations.
Accordingly, favourable epidemiological findings do not rule out adverse health effects from excluding animal products. It is also worth noting that epidemiological findings do not universally support advantages of vegan diets, including evidence suggesting disadvantages for bone health and colorectal cancer risk.[49] [50] [51]
In principle, the risks associated with the nutritional challenges discussed above can be substantially reduced through appropriate food choices and supplementation. However, there is also considerable uncertainty about other potential long-term health effects of completely eliminating animal-source foods, which have formed part of human diets over millions of years and have therefore played an important role in the evolution of human physiology.[52] [53] Randomised controlled trials examining the long-term health outcomes of different dietary patterns are generally not feasible.[54] As a result, our understanding of vegan diets relies largely on observational studies, making it inherently difficult to distinguish correlation from causation and to draw robust causal conclusions.
Therefore, meeting currently established nutritional requirements does not eliminate the possibility of health risks that are not yet fully understood. Further research is needed to reduce these uncertainties over time and identify ways of addressing any additional risks that emerge.
The nutritional challenges and uncertainties discussed in the Nutrition Review do not mean that vegan diets cannot be healthy or are not worth pursuing. Nor does it imply that standard Western diets are free from significant health challenges and uncertainties. Rather, it reinforces the case for a more evidence-based narrative around vegan diets that helps people navigate the nutritional challenges we already understand, remains honest about the uncertainties that remain, and creates stronger incentives to reduce both over time. Ultimately, a vegan movement that takes the challenges and uncertainties of vegan diets seriously will be better equipped to overcome them.
Throughout, “vegan diet” refers to a diet that excludes all animal-source foods, without implying adherence to the broader ethical philosophy of veganism. I use this term rather than “plant-based diet” to avoid ambiguity.
In the 2014 Faunalytics Study of Current and Former Vegetarians and Vegans, the largest study of veg*n dietary lapse to date, health was the second most commonly stated reason for abandoning the diet (26%), after dissatisfaction with the food (32%). In the 2022 Faunalytics study Going Vegan or Vegetarian: Barriers and Strategies on the Path to Success, new veg*ns who felt unhealthy on their diet were more than three times as likely to abandon it within six months (30% vs 8%), regardless of initial motivation. Once people felt unhealthy, providing health information did not seem to prevent them from abandoning their diets, highlighting the importance of reaching people with accurate information before problems arise. Notably, there appears to be little quantitative research examining why people abandon vegan diets specifically, which represents a significant evidence gap.
This does not necessarily mean that these groups are most likely to have nutritionally inadequate diets. For example, young adults with busy lifestyles may face greater practical barriers to careful dietary planning and may therefore also be at meaningful risk, even if the potential consequences of nutritional inadequacies are generally less severe for them.
Das, J. K., & Padhani, Z. A. (2022). Alleviating hidden hunger: an infallible bridge to improved health and nutrition. The Lancet Global Health, 10(11), e1539–e1540. https://doi.org/10.1016/S2214-109X(22)00421-1
For example, several high-profile celebrities have stopped being vegan and publicly cited health problems as a reason, including Angelina Jolie, Anne Hathaway, Liam Hemsworth, Miley Cyrus, and Zac Efron. Such cases can attract considerable attention and contribute to negative perceptions of vegan diets.
Fairly or not, poor health outcomes among vegans are generally seen as a problem with veganism itself, whereas poor health outcomes among omnivores are commonly attributed to the particular implementation of the diet, not to eating animal products per se. For example, several cases of malnourished vegan children in Italy received widespread media attention and prompted a broad public backlash against veganism in 2016.
For example, philosopher and YouTuber Alex O'Connor, who had publicly advocated veganism for several years, began eating animal products again after finding that his specific circumstances made it difficult to maintain a healthy vegan diet. Despite continuing to strongly support animal advocacy and the end of factory farming, he described receiving "a great deal of hatred and vitriol" from parts of the vegan community and worried that such reactions could alienate people considering veganism.
For example, several plant-based meat producers responded to health concerns around ultra-processed foods by reducing or removing certain additives, illustrating how consumer pressure can play an important role in driving product development.
The widely used food-scanning app Yuka provides an early example of this dynamic. Its relatively simple health scores already have an impact on consumer expectations and product development: in a 2025 survey of 200 French food industry professionals, 78% said that Yuka scores influence the formulation of their products.
This does not mean that all of the challenges and uncertainties should be communicated in every context. The appropriate emphasis and level of detail may vary depending on the audience and communication goal. However, messaging should always remain consistent with the overall narrative.
For example, Gallup polling found 2% of US adults identifying as vegan in 2012, 3% in 2018, and 1% in 2023, and YouGov's British tracker similarly shows vegan identification fluctuating between 2% and 3% from 2019 to 2026.
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The AND's position paper on vegan diets was authored by Susan Levin, Vesanto Melina, and Winston Craig. Susan Levin worked at the time for the Physicians Committee for Responsible Medicine (PCRM), an organisation whose stated mission includes saving animal lives through plant-based diets. Vesanto Melina earned part of her livelihood by publishing books and teaching courses on vegan nutrition and repeatedly cited her own book, "Becoming Vegan", as a source in the position paper. Finally, Winston Craig was a Seventh-day Adventist and professor at Andrews University, a Seventh-day Adventist institution that explicitly promotes the church's longstanding emphasis on vegetarian nutrition.
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The Impossible Burger is a notable exception, as it contains heme iron from soy leghemoglobin produced through precision fermentation.
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The 2014 Faunalytics Study of Current and Former Vegetarians and Vegans found that 84% of people who had ever followed a vegetarian or vegan diet had abandoned it. More recently, a 2025 US YouGov survey found that 1.37% of respondents had followed a vegan diet for at least three years but were now neither vegetarian nor vegan, compared with 2% who were currently vegan. The percentage of ex-vegans would naturally have been higher if the survey had also included those who had followed a vegan diet for shorter periods.
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