A French study has revealed that the real secret behind the heart-health benefits of a plant-based diet lies in the quality and level of processing of the foods consumed. Diets rich in minimally processed, nutrient-dense plant foods were linked to a 40 percent lower risk of cardiovascular disease, while those high in ultra-processed plant products showed little or no benefit and, in some cases, an increased risk.

Conducted by France's National Research Institute for Agriculture, Food and Environment (INRAE), Inserm, Université Sorbonne Paris Nord, and Cnam, the study analysed data from 63,835 adults as part of the French NutriNet-Santé cohort, with findings published in The Lancet Regional Health – Europe.

Researchers found that adults who regularly consumed fresh or lightly processed fruits, vegetables, legumes, and whole grains had a significantly lower risk of developing cardiovascular disease compared to those whose diets relied more heavily on ultra-processed plant-based products, such as industrial breads, packaged soups, or ready-made meals.

The results highlight that not all plant-based foods offer equal benefits and emphasise the need to consider both nutritional quality and the degree of processing when assessing the health effects of plant-based diets.

The study supports public health strategies promoting plant-based foods of high nutritional value with minimal industrial processing, such as fresh, frozen, or high-quality canned fruits and vegetables free from added fats, salt, sugar, or additives, to improve heart health and reduce the risk of cardiovascular disease.