Eating healthy has always been associated with eating natural, if boring, foods and staying away from the tastier, fatty and at the extreme the more fried the better. Most serial carnivores would also acknowledge that eating your vegetables is healthier, and eating nothing but vegetables the healthiest. But new findings are connecting eating an all-plant diet (aka vegetarianism) with depression.
ALL MALE STUDY OF VEGETARIANS LINKS NO MEAT TO DEPRESSION, NO ONE AT ALL SURPRISED
So far the study making this connection does have some real limitations as it was conducted with male subjects only. But it has some traction as vegetarians and vegans are likely deficient in many vitamins, minerals and fatty acids that are essential to many biological functions, the least of which is neurological function. So as we already know even if we don’t practice it, it’s always a good idea to supplement our diets with those important components that might be missing.
The authors, from the University of Bristol and the NIH, looked at data from 9,700 men in Britain—all were the husbands of pregnant women taking part in a long-term study on parent and child health. The men indicated whether they were vegetarian and vegan, and filled out questionnaires about the specific makeup of their typical diets.
STUDY HINTS AT THAT THE LONGER MEN ARE VEGETARIANS, THE MORE DEPRESSED THEY ARE
Men who were vegetarian/vegan, of which there were only 350 total (the team lumped the two groups together, since there weren’t many vegans), were more likely to have depression than non-vegetarians, and more likely to have a higher depression score. Even after adjustment for potential confounding variables (like family history, number of children, job status, and so on), the connection still held. There was also a slight connection between the number of years one had been vegetarian and the severity of one’s depression, but that link wasn’t statistically significant.
VEGETARIANS MORE LIKELY TO CONSUME MORE POISON PESTICIDES AND ESTROGENS
Despite the obvious health benefits of vegetarianism, there are some good reasons that vegetarians and vegans might be prone to depression. Their intake of omega-3 fatty acids, vitamin B12 and folate may be lower than meat eaters’, the authors write, and deficiencies of these have all been associated with depression. The same may be true for iron and zinc. Additionally, the authors suggest that vegetarians may have a higher intake of omega-6 fatty acids, which have been shown to increase inflammation and have also been linked to depression. Vegetarians and vegans may also consume more plant estrogens, particularly if they eat a lot of soy products. Finally, the authors suggest that vegetarians and vegans may take in higher levels of pesticides, assuming their intake of plant-based foods is higher than average.
UNCLEAR IF VEGETARIANS/ VEGANS BECOME DEPRESSED, OR IF DEPRESSED BECOME VEGETARIANS
The team points out that reverse causation can’t be ruled out—that is, people who are already depressed might be more likely to become vegetarian, perhaps in hopes of treating their depression with diet, or because of ethical or other concerns. Studies like this don’t show causation, just correlation, so it’s hard to know which way the relationship works, or whether it’s a two-way street. The authors also suggest that it’s possible that something else altogether may be “causing” both the vegetarianism and the depression: “It is possible that for some proportion of the population,” the write, “vegetarianism is not chosen for health, religious or ethical reasons, but is a marker for other psychiatric disorders manifesting with symptoms of both eating disorders and depressive symptoms.”
LARGER LINK NEEDED, IN THE MEANTIME TAKE YOUR VITAMINS TO HELP AVOID DEPRESSION
Given that the study was quite small, and will need to be repeated in a much larger sample of both men and women, it’s hard to draw any real conclusions. At the very least, it may be a good reminder to take supplements (talk with your doctor first), if you’re vegetarian, and particularly if you’re vegan, since B12 comes from animal sources only. The authors cite studies finding that depression was reduced, sometimes by up to 50%, in people who started taking B6, B12, and folic acid supplements. Whether you’re veggie or not, getting all the essential vitamins, minerals, protein, and fatty acids you need is clearly key, both for physical and mental health.