Why vegetarians have 20% higher chance of suffering stroke than meat eaters
Oxford University scientists, who tracked nearly 50,000 people for 18 years, believe low intake of the vitamins from meat may cause the additional risk.
The academics found vegetarians and vegans had a 20 per cent higher risk of stroke than meat-eaters.
This is equivalent to three more cases of stroke per 1,000 people over 10 years, mainly due to a higher rate of hemorrhagic stroke – which occur when blood from an artery starts bleeding into the brain.
Vegetarians and vegans in the study had lower circulating cholesterol and lower levels of key vitamins – such as vitamin B12, which could explain the link, the researchers said.
The popularity of meat-free diets is on the rise, with around 1.7million people in Britain now avoiding meat.
However, those avoiding meat also had significantly lower levels of coronary heart disease – which cause heart attacks and angina.
The researchers, writing in the British Medical Journal, said: “Overall, the present study has shown that UK adults who were fish eaters or vegetarians had lower risks of ischaemic heart disease than meat-eaters, but that vegetarians had higher risks of stroke.”
Vegetarians were found to have a 22 per cent lower risk of heart disease than meat-eaters – the equivalent of 10 fewer cases per 1,000 people over a decade.
Pescatarians – those avoid meat but eat fish – had a 13 per cent lower heart disease risk.
The difference may be at least partly due to lower body weight, blood pressure, and diabetes among vegetarians, the authors said. The study looked at data on 48,188 people with an average age of 45 years. Just over half were meat-eaters, while a fifth ate only fish, and a third were vegetarian or vegan.
In the 18 years of follow-up, there were 2,820 cases of heart disease and 1,072 of stroke.
Lead researcher, Dr. Tammy Tong, from the Nuffield Department of Population Health at Oxford, said: “Additional studies in other large scale cohorts with a high proportion of non-meat eaters are needed to confirm the generalisability of these results and assess their relevance for clinical practice and public health.”
Meat eaters were more likely to suffer from heart disease, with experts claiming fans of sausages and steak are likely to be fatter, suffer high blood pressure and cholesterol, and struggle with type 2 diabetes.
In a linked editorial published in the same journal, Professor Mark Lawrence at Deakin University, Australia, said the study’s stroke risk should be kept in perspective.