This piece is part of my “Arguments” series. In this collection of posts, I examine and respond to some of the most common arguments used to defend the exploitation of animals or to criticise veganism.
These articles are not intended to be exhaustive treatments of each topic. Rather, they are designed as practical reference pieces, helping readers reflect on these arguments more carefully and respond to them in a thoughtful, informed way.
You can find other entries in this series here.
The Claim
One of the most common justifications for eating animals is the claim that it is necessary for human health. This belief is widespread, but it is largely based on outdated information and misunderstanding.
Necessities are things that we cannot live without. If humans are able to live healthy lives without consuming animal products, then eating animals cannot accurately be described as necessary.
A substantial body of research demonstrates that well-planned plant-based diets can support good health at all stages of life (1)(2). Major professional organisations, including the Academy of Nutrition and Dietetics and the British Dietetic Association, have both confirmed that appropriately planned plant-based diets are nutritionally adequate (1)(3).
This alone is enough to challenge the claim of necessity. If millions of people can live without animal products, then animal products are not biologically required for survival or health.
The Short Answer
Major health organisations agree that well-planned plant-based diets can support good health at all stages of life.
Millions of people live healthy, active lives without consuming animal products, including high-level athletes. This shows that animal products are not biologically necessary for survival or performance.
Nutritional deficiencies occur in all types of diets, not just vegan ones. They reflect poor planning, not the absence of animal foods. Like any healthy diet, plant-based eating requires basic nutritional awareness, but this does not make it unsafe.
For most people in modern societies, eating animals is a choice, not a necessity. Once this is recognised, the ethical question becomes unavoidable: If we do not need to harm animals to be healthy, why continue to do so?
The Detail
Necessity Does Not Mean “Optimal”
As vegans, we do not need to prove that plant-based diets are superior to all other diets in every respect. To challenge the claim of necessity, we only need to show one thing: That humans can be healthy without consuming animal products. Clearly, we can.
Whether a plant-based diet is slightly better, slightly worse, or roughly equivalent to other healthy diets are separate questions. The existence of healthy vegans already disproves the idea that animal products are required for health.
This point is reinforced by the many plant-based athletes and physically active professionals who perform at elite levels while consuming no animal products (4). High physical performance requires adequate protein, energy, and micronutrients, and this is clearly achievable on plant-based diets.
Addressing Deficiency Concerns
Critics often point to cases of vegans developing nutritional deficiencies as evidence that animal products are necessary. It is true that some people following plant-based diets become deficient in certain nutrients. This should not be denied.
However, deficiencies are also extremely common in people who consume animal products (5). Iron, fibre, vitamin D, and folate deficiencies are widespread in meat-eating populations. Poor nutrition is certainly not unique to plant-based diets, or an inherent part of adopting one.
The existence of nutrient deficient vegans is therefore not an argument against plant-based eating. It is an argument against poorly-planned diets. Keep in mind that a plant-based diet is an umbrella term. Two vegans can have two diets that are radically different from one another, from a whole foods diet to a diet composed mostly of processed vegan faux meat.
A limited diet based primarily of highly palatable processed foods, regardless of whether they contains animal products, is unlikely to support good health. A diet based on whole, varied, nutrient-dense foods is far more likely to do so. Plant-based diets are no exception to this rule.
The Role of Planning and Education
Like many healthy dietary patterns, plant-based diets require some basic nutritional awareness. Key nutrients such as vitamin B12, iodine, and omega-3 fats may require attention (6).
This does not make vegan diets unnatural or unsafe. It simply reflects the realities of modern food systems and nutrition science. Many non-vegan diets also rely on fortified foods, supplements, and industrial processing. These have become a part of our modern food systems. Fortified flour, iodised salt, vitamin D supplements, and enriched cereals are all widely used by meat-eating populations.
Needing some degree of nutritional planning is not evidence that animal products are required, it is evidence that informed eating matters. If you want to learn more about how to plan a healthy, plant-based diet, you can do so through my Nutrition page.
Summary
The claim that eating animals is necessary does not stand up to scientific scrutiny.
Major health organisations agree that well-planned plant-based diets are nutritionally adequate (1)(2)(3). Millions of people live healthy lives without animal products. Deficiencies occur across all dietary patterns. High physical performance is achievable without animal foods (4).
This means that, for most people in industrialised societies, eating animals is a choice, not a necessity. Once this is acknowledged, the ethical question becomes unavoidable: If we do not need to harm animals to live healthy, fulfilled lives, how can we justify continuing to do so?
Bibliography
- Academy of Nutrition and Dietetics. (2016). Position of the Academy of Nutrition and Dietetics: Vegetarian Diets. Journal of the Academy of Nutrition and Dietetics, 116(12), 1970–1980.
https://doi.org/10.1016/j.jand.2016.09.025 - World Health Organization. (2020). Healthy Diet Fact Sheet.
https://www.who.int/news-room/fact-sheets/detail/healthy-diet - British Dietetic Association. (2017). British Dietetic Association confirms well-planned vegan diets can support healthy living.
https://www.bda.uk.com/resource/vegetarian-vegan-plant-based-diet.html - Craddock, J. C., et al. (2016). Performance of vegetarian and vegan athletes. Nutrition Bulletin, 41(4), 355–362.
- Scientific Advisory Committee on Nutrition. (2019). Iron and Health Report.
https://www.gov.uk/government/publications/sacn-iron-and-health-report - Craig, W. J. (2009). Health effects of vegan diets. American Journal of Clinical Nutrition, 89(5), 1627S–1633S.
https://academic.oup.com/ajcn/article/89/5/1627S/4596952
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