Veganism has become increasingly popular for those seeking to take advantage of the potential nutritional benefits of a plant-based diet. How many of us are vegan? Based on 2012 polling data, the Center for Disease Control found that between 2 million and 6.9 million of Americans now identify themselves as vegans. But, recently, scientists have begun to look at exactly how vegan diets alter our hormonal systems. Do vegan diets change your hormones?
Just What is a Pure Vegan Diet?
Eating vegan, in the purest sense, means you avoid all meat and all animal products such as eggs, milk, cheese and other dairy.
In 2006, a poll by the Harris Interactive in which 1.4% of Americans revealed that the demographic of vegans skews younger and more female than the population in general.
Why do people choose to "go vegan"? Reasons the responders gave for for choosing to "go vegan" included the nutritional and health benefits that were believed to be a consequence of plant-based diets, the effect that eating meat had on the environment, the ethical issues that stemmed from eating meat, the attempt to avoid diseases that could be contracted from animal based products, and disagreement with the meat industry's practice of using growth hormones and antibiotics which could potentially have an adverse affect on consumers.
In terms of health benefits, studies suggest that, overall, veganism really is a healthy way to eat. Vegan diets are high in fiber, magnesium, folic acid, vitamins C and E, and iron. Vegan diets tend to have fewer calories and saturated fat.
All this correlates with lower rates of cardiovascular disease, obesity, Type 2 diabetes, and cancer. Not a bad trade-off for giving up burgers and steaks.
What nutrients do you miss out on if you go vegan? In general, vegan diets tend to be deficient in
omega-3 fatty acids (since vegans don't eat fish and the plant sources of omega-3 don't pack as much of these nutrients),
To make up for these deficiencies, you will need to take additional supplements to balanced your diet.
How Vegan Diets Affect Your Hormones
Recent studies have also begun to examine the hormonal effect that a vegan diet may have on the human body.
A study published in the British Journal of Cancer in 2000 by NE Allen, sought to illuminate the hormonal effect caused by a vegan diet in a group of 669 men.
Of the group, 226 were omnivores, 237 were vegetarians, and 233 were vegans.
The study found that levels of the naturally occurring hormone, insulin-like growth factor-I, was significantly lower in those men who practiced strict veganism.
This is a good thing. The accumulation of this hormone in the human body is widely believed to be a substantial contributing factor to developing prostate cancer.
Furthermore, men who develop prostate cancer have been well documented as having insulin-like growth factor-I hormone levels that were 8% higher than normal healthy males.
The vegans of the 2000 study had hormone levels that were 9% lower than their meat-eating counterparts which suggests that a vegan diet can significantly reduce hormone levels of insulin-like growth factor-I and in turn, greatly decrease the risk of prostate cancer.
Another study conducted by FC Bennet and published in the November 1990 issue of The American Journal of Clinical Nutrition, investigated the correlation between differing diets and estrogen levels in women.
Excessively high levels of estrogen have been linked to higher rates of breast and ovarian cancer.
During the study, a group of 39 women were asked to change their diets in order to observe the effect that the change had on their estrogen hormone levels.
One group was allowed to continue eating meat, another was asked to switch to a vegetarian diet that included fish, and the last group was asked to practice a strict vegan diet.
It was discovered that the estrogen levels of those woman who switched to a strict vegan diet were considerably lower than those of the other groups after a period of 3 months.
The study suggested that the drop in estrogen was in part due to a drop in sex-hormone-binding-globilin (SHBG) which causes estrogen to to return to the blood stream instead of exiting the body.
Again, this is a good thing. This drop in SHBG may prevent the accumulation of estrogen in the body which may decrease the likelihood of contracting breast and ovarian cancers.
Here is a word of caution. To get these good results, you have to eat strictly vegan. In both studies, those test groups that practiced strict veganism were more likely to have lowered hormone levels.
Those test groups that practiced vegetarianism, albeit a less strict version that allowed for fish, did not show the same drastic drop in tested hormone levels as the strict vegan groups.
This suggests that although limiting the amount of animal-based products from a diet may be helpful in achieving a small reduction in hormone levels, completely eliminating animal-based products from a diet, as strict vegans do, is the only way to achieve a significant reduction in those hormone levels.
That being said, the correlation between diet and variance in hormone levels is in no way completely understood. More studies need to be performed in order deepen our understanding of the relationship between the two.