From inews.co.uk
Women and children are more at risk from nutrient deficiencies on a plant-based diet
Walk around a supermarket and the growing shelf space given to plant-based foods makes clear the trend is no flash in the frying pan.
But being vegan carries some inherent health risks, especially for women and children, nutrition experts have warned.
Growing numbers of people could see their health impacted because they are failing to get enough vitamins and minerals, according to researchers at a recent medical conference in London.
So, what are the key nutrients that can be lacking in a plant-based diet and why are certain groups more at risk?
Plant-based eating is not just beloved by influencers – it also gets official encouragement.
The NHS Eat Well Guide says that most people should eat less red and processed meat, because they are high in saturated fat, which is bad for the heart. Vegetables such as beans and lentils are suggested as good meat alternatives because they’re low in fat and high in fibre, which most people don’t eat enough of.
Climate campaigners also want us to eat less meat because livestock, especially cattle and sheep, release methane, which is a potent greenhouse gas.
Schools, councils and hospitals are increasingly trying to nudge people into more vegetarian eating through schemes such as meat-free days in canteens.
In fact, the perfect diet that is both healthy and sustainable for the planet is so plant-based that it limits pork, beef and lamb to 100 grams in total per week – about the amount of mince in one portion of bolognaise. This was the conclusion of a panel of experts commissioned by the medical journal The Lancet in 2019.
But for most omnivores, meat and dairy products supply significant proportions of some essential nutrients, said experts at a recent nutrition meeting called the CluB-12 Symposium in London.
Missing nutrients in plant-based diets
Vitamin B12 – essential for making proteins and DNA. Deficiency can cause fatigue, anaemia and cognitive decline. B12 is naturally found almost only in animal sources and so vegans must take a supplement. Vegetarians can also have low levels.
Riboflavin – another B vitamin. It is most often sourced from dairy products, so plant milk fans should ensure they use a fortified product or take a supplement.
Vitamin D – essential for strong bones and immune systems. Most people in the UK become deficient in vitamin D over winter, and so are recommended to take a supplement, regardless of diet.
Iron – essential for making red blood cells. Deficiency can cause anaemia. Best dietary source is red meat. Plant sources of iron are less easily absorbed.
Proteins – involved in every bodily function. Symptoms of protein deficiency include fatigue, poor immune function and bad skin and hair. Protein in meat is of higher quality than protein from plants.
Key vitamin of concern for women
Vitamin B12 is a key nutrient of concern for vegans, as in nature, it is almost only found in meat or dairy products (although it is added to some breakfast cereals).
Deficiency can cause fatigue, anaemia and harm brain cells. Vegans are recommended to take B12 supplements.
Both men and women can become deficient in B12, but women are more likely to have certain risk factors, including pregnancy and childbirth, said Dr Willemina Rietsema, a GP and researcher who advised on recent NHS guidelines on the vitamin. “The baby needs B12 and can grab it even if the mother has little,” she said.
An anaesthetic often given during childbirth, nitrous oxide – also called “gas and air” – destroys B12. This is why people who use nitrous oxide recreationally can get brain damage.
Another B vitamin, called riboflavin, is available from milk and other dairy products, and so people who drink plant milks are particularly vulnerable to its deficiency, said Professor Mary Ward, a nutrition expert at Ulster University. “It may be one of the reasons why younger women particularly have poor intakes of riboflavin, because they tend to veer away from dairy,” she said.
Only some plant milks are fortified with riboflavin. “You really need to be careful, when you’re taking a milk alternative that it is fortified, and if it’s not, then you need to take a supplement,” said Professor Ward.
In a recent study by Professor Ward, her team found about half of women in the UK are deficient in riboflavin, although she did not investigate if their diet was a factor.
Women also lose iron when they menstruate, and so are more likely to get anaemia if they become vegetarian or vegan.
Vegans and vegetarians are usually advised to take iron supplements, but this doesn’t always work because iron from meat is in a different chemical form that makes it easily absorbed by the gut, said Professor Frédéric Leroy, a food scientist at the Free University of Brussels.
Plant-based diets also have high levels of compounds called phytates, which reduce gut absorption of both iron and zinc, another essential nutrient. “In plant based products, the bioavailability of nutrients like iron and zinc is lower,” said Professor Leroy.
Emily Angus, a senior dietitian at the Vegan Society, said: “It is true that the iron provided by plants is less bioavailable, but our bodies adapt to this by absorbing more iron in the intestine. Many plants provide us with iron and zinc. Great sources of both include lentils, pumpkin seeds, kidney beans, chickpeas, peas, nuts and tofu.”
Has plant-based diet been over-egged?
While concerns about the climate aren’t going away, the potential limitations of plant-based eating, especially for women, have started getting more attention in the pages of medical journals.
In 2023, the Swiss-based Global Alliance for Improved Nutrition calculated that the 2019 Lancet diet would lead to shortfalls of four nutrients (iron, zinc, calcium and vitamin B12) for both sexes, and that the deficit was particularly bad for iron in women of childbearing age.
And a recent randomised trial comparing a standard healthy diet to a “sustainable” low-meat diet found the latter raised the number of people who had nutrient deficiencies, including of B12, riboflavin, zinc and selenium.
Another concern is that if women have a vegan diet while they are pregnant or breastfeeding, any nutrient deficiencies will affect their children.
Various European and US medical societies warn against veganism for pregnant or breastfeeding women, and babies and young children.
Doctors are generally more cautious about health risks of any sort for children than adults, because their bodies are developing and growing.
Risk to kids of cognitive damage
When babies and toddlers are still having both milk and solid foods, vegan diets are “generally discouraged” and should only be done under medical supervision, according to the European Society for Paediatric Gastroenterology Hepatology and Nutrition.
“The risks of failing to follow advice [for supplementation] are severe, including irreversible cognitive damage from vitamin B12 deficiency, and death,” said the society’s weaning guidelines.
Other bodies go further. The German Nutrition Society, for instance, recommends against a vegan diet for pregnant and breastfeeding women, children and adolescents as it is “difficult or impossible to attain an adequate supply of some nutrients”.
The British Dietitic Association, on the other hand, says that vegetarian and vegan diets can be healthy at every age and life stage, as long as they are well planned. “Reducing animal-derived foods and choosing a range of plant foods can be beneficial to the planet, animals and our health,” say their guidelines.
When experts disagree, it can be hard for consumers to know which advice to follow. Professor Ward said the right approach may be to try cutting down on meat rather than cutting it out.
“We’ve got to be careful as we move to more sustainable diets that we don’t make nutrient deficiencies worse,” she said. “I like to think about a plant-rich diet, rather than a plant-based diet.”
https://inews.co.uk/news/science/why-vegan-more-risks-women-children-3934459
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