China (Agencies): According to a study published in the Journal of Agriculture and Food Chemistry, the vegan lifestyle may increase people's risk of blood clots and the hardening of arteries - conditions which can lead to heart attacks and strokes.

The study out of Hangzhou, China, was based on a review of dozens of articles on the biochemistry of vegetarianism published over the last 30 years. While meat eaters have significantly higher cardiovascular risk factors than vegetarians, the study noted that vegans tend to have elevated blood levels of homocysteine, an amino acid related to a higher risk of coronary heart disease, and decreased levels of HDL, also known as "good" cholesterol.

The vegan diet -- which eliminates meat and all animal products including eggs and cheese -- tends to lack key nutrients like iron, zinc, vitamin B12 and omega-3 fatty acids, which can lower the risk of heart-related diseases. Omega-3 fatty acids have been shown to decrease the risk of arrhythmias, or abnormal heartbeats, slow the growth rate of plaque and lower blood pressure.

The study recommends that both vegetarians and vegans up their intake of these nutrients, either through food sources or nutritional supplements. Good sources of omega-3 fatty acids include salmon and walnuts while vitamin B12 is found in seafood, eggs, and fortified milk (including soy milk).