Vegans may require additional omega-3 fatty acids and vitamin B12

According to a new review, people following a vegan diet low in omega-3 fatty acids and vitamin B12 may have a high risk of developing blood clots and atherosclerosis.

In a review of data accumulated over 30 years of studies on the biochemistry of vegetarianism, it has been shown that vegetarians and vegans have lower concentrations of serum vitamin B12 and omega-3 polyunsaturated fatty acid levels in tissue membranes when compared with meat-eaters (1). Thus, they may have a higher risk of developing blood clots and atherosclerosis – both of which increase the risk for heart attacks and stroke. As such, researchers suggested that an increased intake or supplementation of omega-3 fatty acids and vitamin B12 may help to alleviate such risks.

The scientists also noted that meat eaters are known to have a significantly higher incidence of certain cardiovascular risk factors when compared with vegetarians. Such risks include increased body mass index, waist to hip ratio, blood pressure, plasma total cholesterol, and serum lipoprotein concentration. However, people following strict vegetarian and vegan diets are not be immune to cardiovascular risk, as their diets tend to lack several key nutrients, including iron, zinc, vitamin B12, and omega-3 fatty acids. Previous study findings suggested that vegetarians and vegans who do not take vitamin B12 supplements often may have abnormally low serum concentrations of vitamin B12, which has been shown to significantly correlate with higher plasma homocysteine levels and potentially be linked to an increased thrombotic and atherosclerotic risk

1. Li D. Chemistry behind Vegetarianism. Journal of Agricultural and Food Chemistry. 2011; 59(3):777–784.