This week marks national vegetarian week, which leaves us pondering whether we should all go veggie for the sake of our health. Of course, any such decision is driven by a constellation of ethical, moral, environmental, and health considerations, but I’m going to stick to my patch, and take a look purely at the nutritional (and by default, health) arguments, and pose the question: are vegetarian diets better for our health?
According to the prestigious American Dietetic Association “appropriately planned vegetarian diets, including total vegetarian or vegan diets, are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases” (1). That’s quite some ringing endorsement. But how well does the evidence stack up?
A cursory look at the data makes for gratifying reading; vegetarians have less heart disease, lower LDL cholesterol, less hypertension, less diabetes, less obesity, lower rates of cancer, and greater life expectancy, than their meat-eating counterparts (2). Against the backdrop of a modern society blighted by chronic disease, it’s quite an impressive who’s who of health benefits.
Whilst that’s all very encouraging, there’s an important caveat; most of the studies into the health benefits of vegetarian diets are observational studies. These involve following large populations, which include both vegetarians and non-vegetarians, over many years and observing their health outcomes; and as we’ve seen, it’s the vegetarians who come out on top. The problem with this type of research is that it is beset by something called ‘confounding factors’. In this case, it is very likely that vegetarians are generally health conscious people and likely express a whole range of healthy behaviours that make them different to non-vegetarians, aside from whether or not they eat meat. Researchers try to ‘control’ for these, but it’s nigh on impossible to do this completely. To cut to the chase, it means it’s impossible to say whether the better health of vegetarians is purely down to their diet, or some other aspect or aspects of their lifestyle.
If we dig a bit deeper, we find that vegetarian and vegan diets typically contain greater abundance of health-promoting plant foods. Here, we’re talking about fruits and vegetables (do I really need to list the health benefits of these?), wholegrain cereals (protective against heart disease, obesity, diabetes, and certain cancers), legumes (linked with less risk of heart disease, diabetes, and obesity) and nuts (regular consumption of which appears to powerfully reduce cardiovascular disease risk). Packing away more than their share of these foods, it’s little wonder that vegetarians and vegans boast better health stats than their omnivorous counterparts, especially those consuming a low-grade Western diet of refined grains, sugars, trans fats, fast food and high energy dense snacks.
But here’s the rub. Despite containing all that good plant matter, vegetarian, and especially vegan diets, can be lacking key components of a truly optimal diet. This can include the long-chain omega-3 fats EPA and DHA typically found in oily fish (so important for cardiovascular health, controlling inflammation, and brain health), vitamin B12 (which amongst other things, helps us get rid of homocysteine, a toxic by-product in the blood that increases risk of cardiovascular disease), trace minerals such as iron, iodine, zinc and selenium, and in purely plant-based diets, vitamin D and calcium needed for bone health. Indeed, following a purely plant-based diet, without proper regard to securing a sufficient intake of these key nutrients, can spell trouble for heart, brain, hormonal, bone, and immune health.
Where does that leave us? What’s certain is that anyone eating a standard modern diet of ‘beige’ and refined fodder, would do well to take lessons from those who consume a more fibre-rich, phytonutrient-packed, plant-based diet. Michael Pollan’s dictum to, “Eat food. Not too much. Mostly plants” rings true. We should all be striving to eat a diet that contains plenty of plant-based foods. Yet, taken to the extreme this principle can back-fire, and purely plant-based diets run a big risk of nutritional deficiencies. In fact, as we explore in more detail in our award-winning book The Health Delusion, carefully chosen animal-based foods can elevate the nutritional status of even the best vegetarian diets.
If you are committed to avoiding animal-derived foods (and who could question the ethics of that?), then planning your diet carefully, plus appropriate use of nutritional supplements and/or fortified foods, will help ensure sufficient intake of vitamin B12, vitamin D, calcium, iron, zinc, iodine, selenium and omega-3 fats, allowing you to reap the fullest possible health benefits from a plant-based diets.
(1) Craig WJ et al (2009) Position of the American Dietetic Association: vegetarian diets. Journal of the American Dietetic Association 109(7):1266-82
(2) Fraser GE (2009) Vegetarian diets: what do we know of their effects on common chronic diseases?American Journal of Clinical Nutrition 89(5):1607S-1612S
(3) Key TJ et al (1996) Dietary habits and mortality in 11,000 vegetarians and health conscious people: results of a 17 year follow up. British Medical Journal 313(7060):775-9
Glen has a Masters Degree in Nutritional Medicine, and is also trained as a Nutritional Therapist, graduating from the Institute for Optimum Nutrition (ION).
Glen’s work spans private practice, corporate consultancy, lecturing, writing and broadcasting, including numerous TV appearances. Glen is an established writer who contributes to a number of publications, and is the author of two books, The 100 Foods You Should Be Eating and The Health Delusion. Glen is co-founder and director of the pioneering health information blog HealthUncut.com and is an expert blogger for the Huffington Post.
Glen focuses on the importance of taking an individualised approach to promote optimal health, focusing on the underlying causes of health problems, rather than just the symptoms. Glen provides his clients with comprehensive, personalised and highly sophisticated nutritional programmes, reflecting the latest scientific evidence and current thinking.
Glen holds regular nutrition clinics at KX gym.