VEGAN and vegetarian diets are linked to a lower risk of heart disease but may increase the risk of stroke, experts say.

A study from Oxford University found that people who follow the diets have a 22per cent lower risk of heart disease than meat eaters, while pescetarians have a 13per cent reduced risk.

However, researchers also found that vegetarians and vegans were a fifth more likely to suffer a stroke than meat eaters, which they suggest may be partly due to a lack of vitamins.

The study included data for 48,188 people with no history of heart disease or stroke at the start of the study.

The group was split into 24,428 meat-eaters, 7,506 people pescetarians, and 16,254 vegetarians or vegans.

Over a follow-up of 18 years, 2,820 cases of ischaemic heart disease and 1,072 cases of stroke were recorded.

After adjusting for factors that might influence the results, researchers found that fish-eaters had a 13per cent reduced risk of heart disease than meat eaters, while vegetarians and vegans had a 22per cent lower risk. This was equivalent to 10 fewer cases of heart disease in vegetarians and vegans than in meat eaters per 1,000 people over 10 years.

But the study also found 20per cent higher rates of stroke in vegetarians and vegans, equivalent to three more cases of stroke per 1,000 people over 10 years.