Question marks raised over the vegetarian diet

Last week I wrote a piece which attempted to highlight the nutritional attributes of meat (and there are many). I appreciate that not everyone want to eat meat. Some don’t like to eat it, and some will not eat it on moral, ethical, animal welfare or religious grounds. Let me state here that I have no objection to any of this. I just think for those of us who do eat meat, it’s not a bad thing to know just how nutritious and potentially health-giving this food can be (despite what conventional nutritional wisdom may tell us).

I also believe that it’s not a bad thing for vegetarians to be aware that the omission of meat and fish from the diet can put them at risk of certain nutritional deficiencies. These were highlighted in a recent piece published in the journal Nutrition in Clinical Practice [1]. This piece specifically highlights the fact that vegetarian diets tend to be low in vitamin B12, vitamin D, omega-3 fatty acids, calcium, iron, and zinc. It also recommends the use of “supplements and fortified foods” to provide “a useful shield against deficiency”.

This piece goes on to claim, however, that vegetarians have reduced rates of death from ischemic heart disease; and decreased incidence of hypertension, stroke, type 2 diabetes, and certain cancers than do non-vegetarians. I hear these claims for vegetarian eating a lot, but do they stand up to scrutiny?

The idea that vegetarians enjoy a health advantage over more omnivorous eaters is based on the findings of ‘epidemiological’ studies. These studies may show an association between vegetarianism and improved health, but that does not mean the vegetarianism is causing the improved health. It is possible that any apparent benefits to health that appear to come from vegetarianism may come not from the absence of meat and fish from the diet, but from other factors associated with vegetarian living such as a reduced tendency to smoke and healthier exercise habits. These so-called ‘confounding’ factors need to be taken into consideration in order to make a fair assessment of the relative merits of vegetarian and non-vegetarian diets.

Some researchers have attempted to make a more accurate assessment of the benefits (or otherwise) of vegetarian eating by taking into account these confounding factors. In one study, researchers attempted to counteract any confounding factors by focusing only on individuals who shopped in health food stores. The idea here is that all of these individuals are generally ‘health-conscious’, whether they are vegetarian or not. This allows a fairer appraisal of the impact of vegetarian or non-vegetarian eating. This study found that compared to the general population, death rates in vegetarians and non-vegetarians were significantly lower than in the general population (which supports the notion that health food shoppers are a generally health-conscious bunch). However, overall risk of death in vegetarians and non-vegetarians the same [2].

In another study, vegetarians were asked to recruit their friends and family into the study. Doing this was thought to help ensure that all individuals in the study were similarly health-conscious. Again, this study found that vegetarians and non-vegetarians had risk of deaths lower than that of the general population. However, again, death rates for vegetarians and non-vegetarians were essentially the same [3].

And in another piece of research comparing vegetarians and non-vegetarians, quite detailed analysis of the dietary habits of some 56000 individuals was undertaken [4]. This study, yet again, found that the overall risk of death in vegetarians was not lower than in non-vegetarians.

And what of that claim about vegetarian diets being better for the heart? None of these studies found any evidence for this contention either.

So, the plain facts show that, overall, there is no broad health advantage to be had from eating a vegetarian diet. In other words, while individuals may be unkeen to eat flesh foods on moral, ethical and religious grounds, there does not appear to be a good argument for vegetarianism on grounds of health.


1. Craig WJ. Nutrition concerns and health effects of vegetarian diets. Nutrition in Clinical Practice. 2010;25(6):613-20

2. Key TJA, et al. Dietary habits and mortality in 11000 vegetarians and health conscious people: results of a 17 year follow up. Br Med J 1996;313:775-9

3. Thorogood M, et al. Risk of death from cancer and ischemic heart disease in meat and non-meat eaters. BMJ 1994;308:1667-70

4. Davey GK, et al. EPIC-Oxford: lifestyle characteristics and nutrient intakes in a cohort of 33,883 meat-eaters and 31,546 non meat-eaters in the UK. Public Health Nutr 2003;6:259-68

35 Responses to Question marks raised over the vegetarian diet

  1. Mary Lomax 7 January 2011 at 1:57 pm #

    So would it also seem from these studies that vegetarians need not be overly concerned about the nutritional deficiencies of their diet if they appear to be no more unhealthy (or at least no more at risk of dying) than their similarly health conscious meat eating counterparts?
    I also wonder how the average meat based diet stacks up for nutrient content – and deficiencies?
    Personally I see eating or not eating meat as more of an ethical consideration than a health one.

  2. Sandra Easton 7 January 2011 at 3:35 pm #

    The title of this item is misleading: it suggests that there are problems with the diet, whereas the article is saying the benefits may be overstated. That’s not the same thing. It’s nice to know, but then, as Isaac Bashevis Singer said, ‘I did not become a vegetarian for my health: I did it for the health of the chickens’.

  3. Bob 7 January 2011 at 7:19 pm #

    How can a vegetarian diet be healthier if one has to take supplements?
    Did we evolve eating supplements?

  4. Elaine 7 January 2011 at 7:33 pm #

    Sorry, I don’t understand what question marks are raised? The title doesn’t reflect the article, as there balance of the article seems to say that the vegetarian diet is as healthy (or more healthy, in the first article).

    The first meta analysis that came up on Google (taking into account similar lifestyles, as above) was “Mortality in vegetarians and nonvegetarians: detailed findings from a collaborative analysis of 5 prospective studies” (Key et al, Am J Clin Nutr September 1999 vol. 70 no. 3 516S-524S) and found that regular meat eaters with similar lifestyles had higher risk of dying from heart disease but no increased mortality risk from other diseases they looked at.

    Just think people should know what the research says. From what I can gather, a vegetarian/ vegan diet is healthier (even if only slightly), better for animal welfare and better for the environment (carbon, water, runoff pollution, etc).

    I didn’t mean to go on so much! It has definitely started a healthy debate…

  5. Rog Davis 7 January 2011 at 9:11 pm #

    The article is misleading in it’s title. Reading through the article there it claims no advantage or disadvantage to being a vegetarian amongst those that are similarly health conscious, this doesn’t make a vegetarian diet and worse nutritionally than a typical meat eaters diet.

    There are vegetarians and meat eaters that fail to eat balanced diets. And as the article mentions the increased awareness in being vegetarian does have significant health benefits whether these are as a direct result of the diet or not. Further more there is plenty of research supporting the links between high meat diets and digestive cancers.

    Whilst I would be the first to agree a diet containing meat a few times a week would be ideal nutritionally very few meat eaters can do this. Most over eat meat to a point that they are risking their health.

    In addition to any moral aspects, there are also many further issues, such as the worlds inability to provide enough food for everyone to eat meat in the way developed countries do (meat is very inefficient to produce). This information is readily available and has even been addressed in UN reports

  6. Paul Anderson 7 January 2011 at 9:18 pm #

    It certainly seems to me that eating meat is as much a moral question as it is a health question for many people. But if no one ate meat who would keep animals. If everyone was vegetarian there would be very few pigs or cattle. And if everyone was vegan there would be very few chickens.

    My own view is that unprocessed food is best – vegetarian of otherwise. Grass fed meat and less intensively farmed is probably optimnal for viatmin and mineral content and for absorbtion of fat soluable vitamins.

    Probably best to avoid lectins and gluten as well.

    I think this particular piece is as much a general comment on the worth of epidemiological studies as it is a comment on the health benefits or drawbacks of a vegetatarian diet.

  7. drdrm 7 January 2011 at 9:21 pm #

    This post could just as well have been entitled
    “Question marks raised over NON-vegetarian diet

  8. Valerie H 7 January 2011 at 10:10 pm #

    Our current methods of farming are not sustainable for the long term. Anything produced using conventional farming methods uses chemical and petroleum based fertilizers, pesticides and herbicides. Animals in concentrated factory farms produce pollution and the meat is less healthy. Animals raised on pasture are not consuming grain. Their food doesn’t make them sick, so antibiotics are not needed.
    Vegetarianism can be better for the environment, provided that the food is grown organically. However, in order for the soil to be in top condition, animal waste compost is vital. We cannot live without animals in our lives in one way or another.

    A truly sustainable diet provides all the nutrients needed without supplementation. The cultures that have vegetarian diets such as in China and India also have very complex medical systems to combat the chronic illnesses.

  9. kate 7 January 2011 at 10:55 pm #

    Definitely, a visit to pubmed (google ‘pubmed’) should provide HOURS of fun looking at the results of a search for ‘vegetarian mortality.’ Needless to say, there are so many studies and related studies that you can spend days, not hours, looking at the results.

    Try to find a similar wealth of information about ‘meat-eaters’ and all the various benefits of someone who eats ONLY meat and – good luck with that.

  10. IW 7 January 2011 at 11:11 pm #

    The ethical considerations of eating meat or not eating meat can be far deeper and more confusing than it seems. For example, most vegetarians still get a large portion of their food from the grocery store, where it, in turn comes from large farms. Even organic produce and grains often comes from big agricultural operations headed by surprising names. These organic crops are often grown as monocultures, destroying the integrity of the soil and leading to Mississippi River run off (at least in the United States) that goes into the Gulf to create the present “dead zone”. This in turn affects the lives of countless organisms in the ocean and the soil. Not to mention, that there really is no such thing as a vegetarian diet, because many animals die in the tilling of soil and other farming processes. Pasture grass, however, is one of the most effective things at absorbing co2 and pasturing animals mean the animals complete a natural cycle over the land, thereby vastly helping the soil quality. One healthy animal can go a long long way towards feeding a family. It really has become clear to me recently that there is (even if you are buying from farmers markets) no diet that doesn’t involve killing organisms, it’s just a matter of size. It’s also become clear to me that vegetarianism is not necessarily the best answer for a healthy ecosystem and planet, but that ruminants are very key. So, I am going to spend my money on meat raised to best quality and try to be frugal in the way I use it – i.e. making stock from bones from a gnawed on chicken leg and carcass. I avoid as best I can factory farmed meats. I sincerely think this is the most effective way to honor the animal kingdom – to be in tune with the path Mother Nature devised, as opposed to coming up with our own failing systems.

  11. Lori 7 January 2011 at 11:16 pm #

    Vegetarians are a self-selected group. People who don’t do well on it are likely to go back to eating meat. With that in mind, an observational or meta-study won’t show that vegetarianism is as good as omnivorism for people in general.

    I’ve experimented enough with my own diet to know that I, for one, would feel lousy as a vegetarian. If others enjoy good health avoiding meat, then by all means they should continue doing so.

  12. Kay Grant 7 January 2011 at 11:28 pm #

    A vegan diet is lower in animal fats and higher in iron than a vegetarian diet. Vegans are also often forced to scrutinise their nutritional intake more carefully than vegetarians. The more varied protein choices required of a vegan diet (eg beans, nuts and seeds) often lead to more varied recipes, and less reliance on chunks of cheese, for example, to satisfy.

    It would be interesting to see a study comparing omnivores to vegans for a more sophisticated mapping of mortality rates.

  13. Bill 8 January 2011 at 12:04 am #

    Elaine says:
    “From what I can gather, a vegetarian/ vegan diet is healthier (even if only slightly), better for animal welfare and better for the environment (carbon, water, runoff pollution, etc).”

    None of this is as simple as it seems. The exact opposite may be true—even, counterintuitively, for animal welfare. For an extremely well-written rebuttal to these ideas, see Lierre Keith, “The Vegetarian Myth.” If you’re a vegetarian, reading this book takes some courage.

  14. Ben 8 January 2011 at 12:23 am #

    I also recommend Lierre Keith’s book. She discusses quite strongly the nutritional problems associated with vegetarianism. But more importantly she discusses why both the moral and ethical arguments for vegetarianism do not stand up either. There is no way to grow healthy plants in the long term for consumption without input from animals – either as compost derived from decaying animal matter or from fertilisers made from fossil fuels – which is essentially decayed animal matter! Plants have been consistently shown to grow better on decaying animal matter than decaying vegetable matter. If animal matter is not used then the soils typically become depleted and the plant harvests drop and become nutritionally deficient. That will not solve world health or hunger.

  15. Jane 8 January 2011 at 12:32 am #

    Just as an aside, and I know it’s anecdotal,but my many vegetarian friends do eat fish which, of course, makes them not vegetarian at all. I do wonder if the studies take account of this in their sampling (I haven’t read them). I would think that if people call themselves vegan, they probably are. Not the case for a lot of vegetarians.

  16. LeonRover 8 January 2011 at 12:38 am #

    Thank you for your blogpost on these Epidemiological Studies.

  17. David 8 January 2011 at 2:03 am #

    Clin Chem Lab Med. 2009;47(3):334-8
    “It is often advocated that a vegetarian lifestyle could reduce the burden of CAD. However, in spite of a majority of Indians being vegetarians, the incidence of CAD is highest in this population”

  18. David 8 January 2011 at 2:27 am #

    You might also read the book “The Vegetarian Myth: Food, Justice, and Sustainability” by Lierre Keith a reformed vegan who does a good job outlining all the health risks associated with being vegan and the impact being vegan has on the environment.

  19. Jeff 8 January 2011 at 2:56 am #

    I think this leaves way too much information out of the equation. For example, the article doesn’t mention at all the amount of processed foods these folks are eating. I would think that the vegetarians are going to be eating less than the typical omnivore, even if they are “health conscious”. Also, where is the meat coming from? Factory farms feeding their animals unnatural things and making them live in unnatural conditions, or are they (for beef) grass fed and allowed to roam and graze naturally? Point is, these are all factors (among many others) that will weigh fairly heavily in on diseases and death and need to be accounted for to truly understand what is healthy and what isn’t.

  20. Norma 8 January 2011 at 10:10 am #

    I’d certainly prefer to be vegan on ethical grounds if I could work out a truly low carb way of doing this ( which did not rely on soya / tempeh / seitan products). For me, and with the greatest respect to my vegetarian friends, the exploitation and deaths of animals required by large scale milk (and therefore cheese) and egg production makes vegetarianism as distressing as most meat production.
    I’d rather eat meat from organic small farms, with animals killed locally than drink milk from a desperately exhausted Friesian, whose calves during her unnaturally short life are prematurely induced and shot at birth.
    But I still accept a cup of tea with milk even though I know the backstory.
    I really struggle with this.

  21. Xavier 9 January 2011 at 1:47 am #

    Subjectively, i find articles such as this one comical and quite annoying given the questions you and others continue to raise that have been answered, and answered resoundingly. Objectively, one can turn to a national best seller that receives almost no attention in mainstream media called “The China Study”, by T. Colin Campbell, and for good reason, as it is a life changing read proving what seems to be common sense, but so uncommon, in the understanding of low animal protein and high vegetable intake. Since it lacks in such recognition by what i presume you (as the author of this article) and majority of the readers you are now influencing , i understand where your doubt in vegetarian/vegan diet stems from. This article only reflects what the general consensus deems vegetarian/vegan diets to be, in a negative light without scientific backing, and if that light scientific evidence such as the resources you have given in your article.

    “The China Study” is an exhausting read into the evidence showing conclusively the strong effects of a vegan, and less so, vegetarian diet. Every so called “question” you have raised is answered, not only by this book, but even by highly appraised resources such as by a presentation by DR. Dean Ornish. This Doctor has even been a guest on Oprah highlighting the overwhelming evidence of high intake of vegatebles with low to no intake of animal protein on heart disease. His studies have proven one can dramatically lower the risk of heart disease AND reverse it by such a diet.

    This article and others are only beating on a horse that is already dead. It is my hope of this post, my first and last one, to dismiss such squandering of time in raising such outdated questions.

  22. helen 10 January 2011 at 6:25 am #

    even if you could stop all the people in the world from eating animals you couldn’t stop the animals eating other animals!! Eat animals or don’t eat animals but stop thinking you are morally superior because you choose to be a vegan or vegetarian eat what you want and let others eat what they want. no one has a right to judge anyone else’s way of eating just get on with your own life and let me live mine!

  23. TokyoMum 17 January 2011 at 5:04 pm #

    The China Study by. T Colin Campbell has been debunked big time. The author has a strong vegetarian agenda. Read to see where went wrong (in other words, lied).

    Be a vegetarian by all means. If your health is at risk, like I used to, meat might just be your saviour.

  24. Carolyn 19 January 2011 at 11:01 pm #

    Has anyone checked what sort of vegetarian diet is eaten though? We have family who call themselves “very strict vegetarians” which causes everyone problems when eating out. However, having seen their choices in food I believe they are non-meat eaters rather than vegetarian, the vegetables they eat are fewer in both variety and quantity than my family and I who are omnivorous. Their choices tend towards carbohydrates and sugars.

  25. Sophie 26 January 2011 at 3:35 pm #

    Omission of fish and meat products in our diet might predispose us to disease. I agree that death rates for vegetarians and non-vegetarians are the same. Because eating a balanced and healthy diet is a must. Deficiencies in some nutrients can reduce our ability to produce enough energy making us feel lethargic and increases our health risks.

  26. Zak 27 January 2011 at 1:12 am #

    I see it as non-meat eating logic. On average, the human intestines are about 5-6 times the size of the person. In comparison, a carnivorous animals digestive tract, such as a cat, is only about 3 times the size of its body. The shorter length allows the meat to pass through the cats’ intestines relatively quickly. It’s commonly believed that the majority of diseases derive from our colons (Dr. John Harvey Kellogg and more recently Dr. Donald Colbert). This is mostly due to the poisons we consume on a daily basis (certain meats included). So wouldn’t you conclude, just using the sheer logic of it, that meat sitting in our digestive tract for a long period of time is be a bad thing? It can take 1-3 days for red meat to be fully digested!

    I believe in consuming wild, organic, grass fed meats in moderation. But the fact is simple, too much of it can pose its dangers.

  27. Jackie Wilkinson 9 March 2011 at 5:13 pm #

    Being a vegetarian doesn’t help the health of chickens. I recently read an interesting piece on Mercola where Jenna Woginrich describes how she stopped being a vegetarian and now owns a small farm where she raises her own chicken, pork, lamb etc. She realized that animal welfare is only improved when people buy and eat well-farmed meat. Her veggie burgers took her out of the battle and did nothing to change farming practices.

    Personally, I support local farmers by buying free range eggs and grass fed beef and I campaign against battery hens and factory farmed cows.

  28. Evan 17 May 2011 at 7:39 pm #

    I don’t think the issue is of meat being intrinsically bad for your health. Clearly, it isn’t. But it is the amount of meat that Americans and much of the West consume that is the issue. Over 200 pounds of meat per person in the US alone is simply not sustainable, both for the planet and our bodies. It’s difficult to pass by, though, when the price of meat is so artificially low due to agricultural subsidies.

    Good meat can be good for your health, but it needs to be eaten relatively sparingly – not everyone can eat like most Americans do.


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