While several studies have shown the beneficial effect of a vegan diet on human health, due to increased consumption of vegetables, fruits, nuts, cereal grains, legumes, and seeds, the increased prevalence of vegan junk food poses a risk of imbalanced nutritional intake.

Recent developments in the food industry have enabled new plant-based meats and dairy substitutes to be created; Among them, a proportion of those are classified as ultra-processed foods. The constituents of ultra-processed foods include additives such as texturizers, dyes, and emulsifiers.

This increased availability of plant-based food alternatives for both vegetarians and vegans is thought to aid dietary planning; though little information is known about the effect of these ultra-processed foods, particularly regarding their nutritional quality and functional effects.

What are ultra-processed foods?

Ultra-processed foods are defined as formulations of substances that are taken from foods (the three major macronutrients starches, fats, and protein isolates) combined with flavors, colors, emulsifiers, and other cosmetic additives. The true definition of the term ultra-processed foods is contested; however, these products have characteristic features which include high energy density, high sodium content, high fat and free sugar content, and poor in vitamins and minerals as well as dietary fiber.

Ultra-processed foods are commonly marketed as healthy, as they fall under the vegan label. These ultra-processed foods fall under the NOVA classification system. The Nova classification was produced in 2014 by Brazil, the first country in the world to release dietary guidelines based on the degree of food processing.

In this system minimally own processed foods were distinguished from processed foods and ultra-processed foods in what is termed as NOVA (‘new’ in Portuguese).

Does the average vegan diet cause negative consequences on health?

Research from the Nutritional Epidemiology Research Team (EREN-CRESS, Inserm, INRAE, Cnam, Université Sorbonne Paris Nord)  analyzed the daily food intakes of 9812 meat eaters, 646 vegetarians, 500 vegetarians, and 254 vegans. The nutritional quality across these diets was assessed by healthy and unhealthy plant-based indices alongside definitive descriptions of these foodstuffs.

Among the four groups, the team found that higher avoidance of animal-based foods was correlated with increased consumption of ultra-processed foods, comprising 39.5% of the energy intake for vegans (33% for meat-eaters, 32.5% for pesco-vegetarians, and 37% for vegetarians). However, when assessing nutritional quality, results demonstrated that this was increased with the level of animal-based food avoidance, with vegans consuming the greatest nutritional quality among the four groups (an index of 67.9; ask compared to 53.5, 60.6, on 61.3 for meat-eaters, pescetarians, and vegetarians, respectively).

This study demonstrated that vegans, vegetarians, and pescetarians consumed greater quantities of both healthy and unhealthy plant-based products; highlighting the heterogeneity in vegetarian and vegan diets. Those consuming a greater proportion of processed forms of plant-based foods are unlikely to benefit from the health benefits attributed to non-processed plant-based foods.

Not all substitutes for non-vegan foods such as meat and dairy are ultra-processed. However, it has been noted that public and academic research into the effects of the increasingly mainstream products is lacking. This is concerning as consumption of these ultra-processed foods is likely to lead to poor health outcomes, which include being overweight, obesity, cancer, cardiovascular disease, type 2 diabetes, and cardiometabolic risks.