These Science-Backed Diets Could Save Millions of Lives and Protect the Climate—Yet Only 1% of Humanity Adopts Them

We live longer than before, but we don't always live better. Today, more and more diseases come from our habits, and in particular from what we eat. What we thought was a personal choice actually has immense consequences on our health and on the planet. Sustainable food is no longer a fringe idea, it is a concrete solution that could change millions of lives.

A food system that harms as much as it nourishes

In less than a century, human food has become one of the main drivers of the environmental crisis. Behind our daily habits lies a system that destroys ecosystems, widens inequalities and fuels growing chronic diseases. According to the international study carried out by Springmann and his colleagues for the EAT-Lancet commission, five major planetary balances are already weakened, notably the climate, arable land, water resources, nitrogen and phosphorus pollution as well as pollutants resulting from human activity such as pesticides or microplastics.

The health impact follows the same trend. One in five people in the world die today as a result of an unsuitable diet. Overconsumption of meat, dairy products, sugar or ultra-processed foods contributes to the rise of cancer, type 2 diabetes and cardiovascular disease. At the same time, 3.7 billion people do not have access to sufficiently diverse food to meet their basic needs. This imbalance weakens health systems and reduces the development potential of millions of children.

The contrast between excess and deficiency sums up the crisis. More than 6.9 billion people eat too much or poorly, while others still struggle to eat properly. Humanity is thus progressing into a nutritional impasse which affects health and the environment in unprecedented proportions.

Sustainable food, a powerful but underestimated lever

To respond to this situation, experts from 35 countries have designed a series of diets capable of improving health while limiting environmental damage. Their proposal is based on a sustainable diet based on an increase in plants and a measured reduction in products of animal origin. These models include several variations adapted to local cultures, whether flexitarian, pescatarian, vegetarian or vegan diets.

The potential for health remains considerable. According to the commission, these diets could prevent up to 11 million premature deaths each year. This would involve a reduction in nutrition-related diseases. The impact would be very marked in rich countries, where excessive meat consumption increases heart risks. In younger regions, such as sub-Saharan Africa or South Asia, the effect would be less strong but would still be beneficial.

The environmental impacts promise to be just as significant. Researchers show that a global transition to these regimes would reduce greenhouse gas emissions by 30 to 50%, reduce the use of agricultural land by up to 70% and significantly limit fresh water consumption. The reduction in demand for meat and dairy products constitutes one of the most powerful levers to slow the degradation of the planet.

Why do so few people eat sustainably?

Despite all these benefits, less than 1% of the world's population today adopts a diet close to these recommendations. The Science Focus article highlights that only a few regions actually achieve this. They often combine culinary traditions rich in plants with good access to healthy products. The best examples come from the Mediterranean basin, the Indian subcontinent and Southeast Asia.

Conversely, the richest countries follow a Western food model, often too rich in meat and processed products. According to researchers, the wealthiest 30% of the world cause more than 70% of food-related environmental damage. This trend worsens inequalities, because the effects on soil, water and climate first affect the most fragile.
Such change requires strong collective choices and in-depth transformations. However, it also offers a unique opportunity. Food could stop depleting the planet and become a lever for a healthier life.