Vegans, vegetarians higher risk of stroke - study

There's a warning for vegans and vegetarians following the release of a major international study.

The study found being vegan or vegetarian could increase the risk of developing stroke.

"It's what we call an observational study. These were just people going about their daily lives, either they were already vegetarian or already meat eaters and we just followed them along," said researcher Kathryn Bradbury.

They analysed more than 48,000 people for 18 years and found vegans and vegetarians had a 22 percent lower risk of heart disease compared to meat-eaters. But they also had a 20 percent higher risk of stroke than them.

There's no definitive reason as to why the vegans and vegetarians in the study had a higher risk of stroke.  But one theory is that they have lower levels of Vitamin B 12 which is mainly found in things like meat and fish.

"Vegetarians will get a little bit if they eat dairy products or eggs. But strict vegans won't get any Vitamin B 12 in their diet so they need to be consuming supplements," said Bradbury.

At Gorilla Kitchen - a plant-based eatery in Auckland - the owner says the study doesn't put her off being vegan.

"There are many factors involved in making the decision to go vegan, including environmental factors, other health benefits for us, and also animal welfare factors," said Rebecca Palmer.

Interestingly, the research found pescatarians - who eat seafood but no meat - had a lower risk of heart disease and no higher risk of stroke.

Other experts say the study's stroke risk needs to be kept in perspective. All participants were from the United Kingdom, so they may not have reflected low to middle-income countries where many vegetarians live.