"It seems that the lower risk of coronary heart disease outweighs the higher risk of stroke if we look at the absolute numbers," says lead researcher Tammy Tong, a nutrition epidemiologist at the Nuffield Department of Population Health at Oxford University.
This is the first study to look at the risk of stroke in vegetarians, Tong said. The study found that vegetarians and vegans have a 20% higher risk of stroke than carnivorous ones, especially hemorrhagic stroke ̵
The exact reasons for this higher risk found in vegetarians are not clear, Tong said. This may be due to "very low cholesterol levels or very low levels of some nutrients," she said.
"There is some evidence to suggest that very low cholesterol levels may be associated with a slightly higher risk of hemorrhagic stroke," she said. Similarly, other studies suggest that a deficiency in some nutrients, such as vitamin B12, may be associated with a higher risk of stroke, Tong said.
However, some researchers are skeptical of the finding of stroke.
The study shows that people who cut meat from their diet are significantly healthier than meat eaters, Dr. Malcolm Finlay, a cardiologist consultant at the Heart Center at Barts, Queen Mary, said at Science University, Science Media reported Center.
But he said the study placed "too much weight on a complex statistical method to try and correct the fact that vegetarians are much healthier than carnivores."
"Although with this method, it can be said that the risk of stroke is not as low as might be expected with vegetarians, given how much healthier they are overall compared to carnivores, their overall risk of major life change cardiovascular events still appear to be much lower, "said Finlay, who did not participate in the study.
There is no significantly higher stroke rate for Pietarians
The Tong research team is followed by more than 48,000 people in the UK, with an average age of 45, who were carnivorous (24,428) , petetarians (7550) and vegetarians, including vegans (16 254). Participants were followed for an average of 18 years and during the study period there were 2,820 cases of coronary heart disease and 1,072 cases of stroke.
The calculations in the study take into account influencing factors such as smoking or physical activity.
People who follow a pestetric diet did not have a significantly higher stroke rate,
This may be due to the fact that fish cholesterol levels are not as low as vegetarians, "Tong explained. They are also unlikely to have vitamin B12 deficiency, "because you can get B12 from fish and other animal products that they eat," she said.
While "vegetarians and vegans have very low consumption of animal products, the only way to get B12 is from supplements or fortified foods," she added.
Vegetarians have a lower risk of heart disease
Vegetarians (including vegans) were found to have a 22% lower risk of coronary heart disease than eating meat from the research team. This equates to 10 fewer cases of coronary heart disease among vegetarians than to carnivores per 1,000 people over 10 years of age.
Pesetarians have a 13% lower risk of coronary heart disease than carnivores, the study shows.