The number of people cutting down on meat and dairy, or cutting these foods from their diets entirely, has been rising over the last decade. The number of vegans in the UK, for example, quadrupled between 2006 and 2018, according to research by The Vegan Society. Even Goa has ventured into this diet.
The vegan diet is generally claimed to be higher in fibre and lower in cholesterol, protein, calcium and salt. The diet still faces confusion and misinterpretation around meat, fish, eggs and dairy cancellations from it.
One of the most common concern is whether a vegan diet provides enough vitamin B12, which is to helps prevent nerve damage, and is found in meat, fish, eggs and dairy, but is not available in fruit or vegetables. It’s recommended that adults consume 1.5 micrograms of the vitamin per day.
“A B12 deficiency can lead to neurological symptoms such as numbness, and it’s irreversible if the deficiency is present for too long,” says Janet Cade, of the Nutritional Epidemiology Group, School of Food Science and Nutrition.
A recent study involving 48,000 people over 18 years compared the health of meat-eaters, pescatarians – who eat fish and dairy but not meat – and vegetarians, including some vegans. They found that people who eat vegan and vegetarian diets have a lower risk of heart disease, but a higher risk of stroke, possibly partly because of a B12 deficiency.
The researchers found that those who didn’t eat meat had 10 fewer cases of heart disease and three more strokes per 1,000 people compared with the meat-eaters. Researcher Tammy Tong, nutritional epidemiologist at the University of Oxford, says the higher risk of haemorrhagic stroke could be for several reasons.
Haemorrhagic stroke is caused by a bleeding in the brain. While low cholesterol is protective for heart disease and ischemic stroke, there’s some evidence showing that low cholesterol levels (associated with the vegan and vegetarian diet) may be linked to a small risk of haemorrhagic stroke.
“Vegans and vegetarians also have a higher risk of B12 deficiency, which may be linked to higher risk of stroke,” she says.
In countries where food isn’t fortified with B12, he recommends vitamin supplements.