My quest for a climate-friendly family diet

“When there’s a discussion about vegan diets or plant-based diets generally, I often feel there’s little attention given to the age group,” says Mary Fewtrell, a professor of paediatric nutrition at University College London. “You’ve got to make sure that the infant and the child get enough of the nutrients that they need to grow and develop properly.”

Younger children have a high requirement for energy micronutrients, and as a result “animal-sourced foods are a good option because they provide all of those nutrients”, Fewtrell says. “If you just give them plants, they’re very high in fibre. It fills them up, and then there’s a risk that they may not then be able to consume enough nutrients because the nutrient density can be very low.”

Fewtrell has co-authored studies that have found vegan and vegetarian children who don’t supplement are at risk of being deficient in Vitamin B12, iodine and iron. These nutrients are more readily available in animal products.

“You could say, well, OK, if they didn’t get the nutrients they need, it might have a short-term effect and you could remedy it. But actually in some cases, it could be irreversible,” she explains. “The one that’s usually cited is [vitamin] B12 deficiency, which can have quite devastating effects on brain development.”

On the other hand, high red-meat consumption in adolescence may increase the risk of breast cancer and a high dairy intake in childhood is associated with colorectal cancer.