Vegan lifestyle can increase risk of heart disease

Vegans may not be immune to heart disease suggest researchers.

Though meat eaters are at higher risk for atherosclerosis, scientists say strict vegetarians may be lacking important nutrients that also put them at risk for heart attack and stroke.

The findings come from a review of dozens of articles published over the last 30 years that suggest a vegan diet supplies adequate protein but may be lacking in iron, zinc, vitamin B12, and omega-3 fatty acids that are important for vascular health.

Researchers say vegans tend to have lower levels of "good" HDL cholesterol and higher levels of homocysteine that put them at risk for heart disease.

Findings from the study, many of which were observational, led the researchers to conclude "vegetarians, especially vegans, could benefit from increased dietary intake of n-3 PUFA and vitamin B12 and thus improve the balance ratio of n-3 to n-6 PUFA and vitamin B12 status" that would in turn reduce the chances of developing blood clots and cardiovascular disease.

The study notes vegetarians generally have a lower risk of heart disease from lower body mass index, lower overall cholesterol levels and lower blood pressure. In the review, researchers found vegans especially have lower B12 levels and lower polyunsaturated fatty acid (PUFA) levels that can lead to a tendency to develop arterial plaque known as atherosclerosis.

The study authors write, "Vitamin B12 is not found in plant foods; however, seaweed may contain vitamin B12 analogues, which can be counted on as reliable sources of active vitamin B12". PUFA - healthy fats - can be obtained from walnuts and certain other nuts or from supplements.

Based on the review, the researchers say there is "strong evidence" that vegans and vegetarians should increase their intake of dietary omega-3 fatty acids and vitamin B12 to lower the chances of heart disease.

J. Agric. Food Chem., Article ASAP: DOI: 10.1021/jf103846u
"Review: Chemistry behind Vegetarianism"