Revealed: What would happen if everyone followed a vegan diet

The researchers believe vegan diets can be healthy on an individual basis, but would be hard to scale up to a national level

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If the entire population switched to a vegan diet it would have a negative effect on public health, a new study claims.

According to research published by the US National Academy of Sciences, everyone turning vegan would likely leave many people deficient in various nutrients.

The researchers set out to examine the impact of the meat industry on greenhouse gas emissions and wanted to find out what would happen if every person in the US adopted a vegan diet.

They found that if all animals were removed from the planet, the amount of food available to humans to eat would increase by 23 per cent. This is because the grains that are currently used to feed animals could be consumed by humans.

This would lead to an increased supply of certain important nutrients, including carbohydrates, copper, magnesium and cysteine. There would actually be more than the population needs.

However the supply of some important nutrients that we now get from animal products would decrease, including calcium, vitamins A and D, B12, arachidonic, eicosapentaenoic and docosahexaenoic fatty acids.

And some of these nutrients have been linked to reduced risk of heart disease, visual and cognitive development in infants, and visual acuity.

“Very simply, there are some nutrient requirements that we cannot get just consuming plant-derived foods,” says one of the study authors Mary Beth Hall, of the US Department of Agriculture’s Agricultural Research Service

“It rather speaks to us evolving as omnivores.”

The researchers did not consider people taking supplements however, only assessing nutritional intake from food alone.

They admit that living healthily on a vegan diet is possible on an individual level, but they believe it would be difficult to scale up.

“It is entirely possible to meet the nutrient requirements of individual humans with carefully crafted, unsupplemented plant-based rations, but this can be a challenge to achieve for an entire population,” the study says.

The researchers also acknowledge that many Americans need to eat more fruit and vegetables, and also that plant-based diets have been linked with many health benefits as well as food sustainability.

They concluded that if everyone were to go vegan, we would need to carefully consider our diets to ensure we receive the right essential nutrients, and some people who wouldn’t have access to a varied enough array of plant-based foods would likely become malnourished.

“When animals are allowed to convert some energy-dense, micronutrient-poor crops (e.g., grains) into more micronutrient dense foods (meat, milk, and eggs), the food production system has enhanced capacity to meet the micronutrient requirements of the population,” the report says.

The researchers suggest that a possible solution could be lab-grown meat.