Processing level of plant-based foods: impact on cardiovascular health

Previous studies have reported that a high consumption of ultra-processed foods[1] is associated with an increased risk of developing cardiovascular diseases, while other studies[2] have shown that a diet including a large proportion of plant-based products—when nutritionally balanced—may reduce the risk of developing these diseases.

In order to study the links between nutrition and cardiovascular health, a research team from INRAE, Inserm, Université Sorbonne Paris Nord, and Cnam went beyond the usual distinction between plant-based and animal-based foods, considering also the nutritional quality—for example, carbohydrate, fat, or antioxidant vitamin and mineral content—as well as the degree of food processing.

The research team analysed health data from 63,835 adults participating in the French NutriNet-Santé cohort. The average follow-up period was 9.1 years, and for those enrolled earliest, it extended up to 15 years. Dietary intake—that is, the foods and beverages consumed over at least three days—was collected using online questionnaires. This detailed data collection made it possible to distinguish between three types of diets, by comparing the proportion of plant-based to animal-based products, and by considering not only their nutritional quality but also their level of industrial processing.

Nutritional quality and degree of processing

The researchers found that adults whose diets were richer in plant-based products of higher nutritional quality (lower in fat, sugar, and salt) with little or no industrial processing had approximately a 40% lower risk of cardiovascular disease compared to those whose diets were lower in such plant-based products and higher in animal-based ones[3].

Adults whose diets were richer in plant-based products of higher nutritional quality but that were ultra-processed—such as industrial wholemeal breads, store-bought soups, ready-made pasta dishes, or commercially prepared salads with dressing—did not have a lower risk of cardiovascular risk compared to those whose diets were lower in such products and higher in animal-based foods.

The risk of cardiovascular disease was approximately 40% higher among adults who consumed a large proportion of plant-based products that were both of lower nutritional quality and ultra-processed—such as crisps, fruit-based sweetened drinks or sodas made from plant extracts, chocolate-based sweets or confectionery, sugary breakfast cereals and savoury biscuits—compared to those whose diets were richer in plant-based products of good nutritional quality with little or no industrial processing.

These results highlight the need to consider both the nutritional quality and the degree of processing and formulation of foods—alongside the plant-to-animal balance in the diet—in order to better assess the links between nutrition and cardiovascular health. They provide new arguments in support of public health and nutrition policies that promote plant-based foods which are both of good nutritional quality with little or no industrial processing (such as fresh, frozen, or high-quality canned fruits and vegetables, for example, without added fats, salt, sugar or additives).