GENEVA - The landmark EAT-Lancet report, published in 2019, laid out how to nourish people and save the planet through a “planetary health diet”, consisting mostly of whole plant-based foods. But new research, published yesterday in The Lancet Planetary Health, suggests the planetary health diet does not provide enough essential vitamins and minerals to nourish the global population. This is even more evident when looking at women of reproductive age (15–49 years) who have increased iron requirements due to menstruation. The planetary health diet provides just 55% of recommended iron intakes for this population.

The research, “Estimated micronutrient shortfalls of the EAT–Lancet planetary health diet,” reveals important dietary shortfalls in iron, zinc, calcium, and vitamin B12. The researchers used new globally representative food composition data and recommendations on harmonised nutrient intakes, both of which were published after the original EAT-Lancet publication. They also adjusted for how nutrients like iron and zinc are absorbed by the body on different types of diets.

Dr Ty Beal, Research Advisor at the Global Alliance for Improved Nutrition (GAIN) and lead author on this publication said, “The planetary health diet is likely to help protect against noncommunicable diseases, which are the leading causes of death and disease worldwide, and to do so sustainably. But these new findings on shortfalls in essential vitamins and minerals are concerning because deficiencies in these ‘micronutrients’ can lead to severe and lasting effects, including compromised immune systems and increased risk for infections; hindered child growth, development, and school performance; and decreased work productivity; all of which ultimately limit human potential.”

The micronutrient shortfalls of the planetary health diet are due to the low amount of animal source foods, which make up just 14% of total calories. To make the planetary health diet adequate in micronutrients would require increasing nutrient-dense animal source foods. In addition, it would require reductions in a compound called phytate, which inhibits absorption of iron, zinc, and calcium. This could be done by reducing the proportion of whole grains, legumes, and nuts—from the baseline planetary health diet, not from current consumption—or, preferably, by reducing the phytate in these foods through crop breeding and processing, including soaking, fermenting, and sprouting.

According to Dr Jessica Fanzo, Bloomberg Distinguished Professor of Food Policy at Johns Hopkins University and co-author, “The challenge in providing enough micronutrients is doing so sustainably. It is not clear exactly how much animal source food, and which types, could be sustainably produced worldwide: experts have different perspectives. But there is a limit. And there will inevitably be trade-offs to grapple with, between human health and environmental sustainability. It is important to use all available approaches to improve diets, including improving diet quality through nutrient-dense foods of both plant and animal origin, and food fortification and supplementation, which have limitations but can help fill micronutrient gaps sustainably and affordably.”

What is clear is that a combination of actions is needed to increase access to diverse nutrient-dense and healthy foods and supplements. This includes increasing their availability, desirability, convenience, safety and affordability through incentives and subsidies, improving fortification policies and implementation; and improving access to healthcare and supplements.

Dr Mduduzi Mbuya, Director of Knowledge Leadership at GAIN concluded, “Future efforts to propose healthy and sustainable diets must ensure micronutrient adequacy, tailor recommendations according to the local context, equitably involve local stakeholders impacted by any changes, and be transparent about trade-offs. Preserving human health and protecting our planet are more important now than ever. All of society must rise to the challenge, now, to address these integrally linked and equally important challenges.”