Ultra-processed plant-based meals linked to higher heart attack risk, French study finds

A large study published in The Lancet Regional Health finds that ultra-processed plant‑based diets are linked to a higher risk of heart disease, challenging the notion that plant‑based eating is universally protective. Researchers tracked more than 63,800 middle‑aged adults in France over an average of nine years to examine how the type and processing level of plant‑based foods relate to cardiovascular outcomes.

Participants who consumed a nutritionally complete, largely unprocessed plant‑based diet were 44% less likely to develop coronary heart disease, while those whose plant‑based diets were dominated by ultra‑processed foods faced a 46% higher risk of coronary heart disease and a 38% higher risk of cardiovascular disease overall. These findings underscore that the heart health benefits of plant‑based eating depend largely on food quality and processing, not merely on avoiding animal products.

The study used the NOVA classification system to categorize foods by the degree of processing. Unprocessed or minimally processed foods include items such as fruit, vegetables, grains, pasta, and fresh or frozen meat and fish, while processed foods add ingredients like salt, sugar or oil to whole foods. Ultra‑processed foods are industrial formulations with multiple processing steps and ingredients not typically found in home cooking, including emulsifiers, flavourings, colourings and preservatives. Researchers said these products tend to be high in energy, added sugar, saturated fat and salt, while being low in fibre and micronutrients. nutritionally healthy plant‑based diets built around unprocessed foods offered the greatest protection against coronary heart disease, whereas no such benefit emerged when plant‑based diets relied heavily on processed or ultra‑processed foods. The worst outcomes were observed in participants consuming ultra‑processed plant‑based diets, whose risk of heart disease rose by nearly 40%. The analysis drew on the NutriNet‑Santé cohort, which enrolled 63,835 adults and assessed diet quality and processing level through repeated dietary records and annual health questionnaires. Foods and beverages, including snacks, were recorded with portion sizes estimated from photographs or standardized containers; nutrient intake was calculated using a validated database and cross‑checked against biomarkers.

Lead author Clémentine Prioux, a nutrition researcher at Sorbonne University, said the findings reinforce the need to advocate not only for reducing animal products but also for encouraging the consumption of minimally processed plant‑based foods to improve cardiovascular health. The researchers stressed that the level of food processing can influence the association between plant‑based diets and cardiovascular disease and noted that the UK, with a wider availability of ultra‑processed plant‑based products than France, could see similar patterns given dietary habits. They added that ultra‑processed animal‑based foods were associated with an even higher risk of heart disease.

The study also highlighted that some people who eat some animal products but avoid ultra‑processed foods do not appear to have an elevated risk compared with those following healthy, whole‑food plant‑based diets. This suggests that combining a balanced approach to plant and animal foods with a focus on overall diet quality may be important for cardiovascular prevention. Researchers accounted for smoking, physical activity and other lifestyle factors, and all foods and drinks were logged to ensure a comprehensive view of participants’ diets and exposures. Finally, the authors argued for considering three dimensions of diet in cardiovascular prevention: the balance between plant and animal foods, nutritional quality, and the degree of processing.

The findings come as health authorities monitor shifting heart disease trends, including rising incidents among younger adults in the past decade. NHS data indicate increases in heart attacks among younger age groups, including a notable uptick in people aged 25 to 29, though experts caution that small absolute numbers can exaggerate percentage changes. The researchers emphasized that while the study is based in France, its implications may extend to other countries where ultra‑processed plant‑based products are widely available. They concluded that dietary guidance should move beyond plant‑based labeling to emphasize the quality and processing of foods as a central component of cardiovascular prevention.

Heart disease remains one of the leading causes of death and disability, though many cases could be prevented through healthier diets and lifestyle choices. The current study adds to a growing body of evidence that the health impact of plant‑based eating depends on processing levels and overall diet quality, rather than on the plant‑based label alone.