Overview. Vegetarians don't eat any food products made from meat, fish, shellfish, crustacea (such as prawns or crab) or animal by-products (such as gelatine or rennet). Vegans don't eat any food products that come from animals, including dairy products and eggs.

Plant-based meats, or meat analogues, are designed to mimic meat products and act as a substitute for meat protein. They are commonly made from plant-based vegetable protein (soy protein, wheat protein, pea and rice protein, or a combination) or fermentation-based fungus protein (mycoprotein).

Unfortunately, due to the highly restrictive nature of the diet, vegans are at risk of being deficient in certain nutrients such as calcium and vitamin B12 usually found in dairy and meat respectively.

No statistically significant differences have been shown for total cardiovascular disease between vegans and meat eaters, but the data so far suggest there may be a lower risk of ischaemic heart disease and perhaps a higher risk of stroke in vegans. There is no evidence of a difference in life expectancy.