A major study analyzing data from over 200,000 U.S. adults suggests that the overall quality of a person's diet is a more significant factor in health outcomes than the level of food processing.

The findings, presented at an annual meeting of nutrition experts in Maryland, indicate that certain ultra-processed foods, including wholegrain breakfast cereals, plant-based milk and yogurt, and supermarket bread, can be incorporated into a healthy eating plan. Ultra-processed foods (UPFs) are typically mass-produced items like snacks, packaged bread, and ready meals, often containing high levels of fat, sugar, and salt, along with artificial ingredients that may affect gut health.

Researchers aimed to differentiate between the overall nutritional quality of a diet and the degree of food processing. They examined plant-based foods within diets over a period spanning from the 1980s to the early 2020s, assessing both their healthfulness and processing level. This focus on plant foods allowed for more consistent comparisons across participants, who included individuals with diverse dietary patterns.

The study found that approximately half of the participants developed heart disease, type 2 diabetes, or died during the study period. Those who consumed healthier diets exhibited a significantly lower risk of these outcomes compared to individuals with poorer-quality diets. Crucially, the researchers observed that it made little difference whether these healthy diets consisted of ultra-processed or minimally processed foods, supporting the idea that nutritional content is paramount.

This challenges classification systems like the widely used Nova system, which categorizes foods by processing level but does not always account for nutritional value. Consequently, some nutritious foods may be labeled as ultra-processed, while some minimally processed items might be high in sugar and offer little benefit.

Xiaowen Wang, a research fellow at Harvard T.H. Chan School of Public Health, commented that while many UPFs are indeed of poor nutritional quality and should be limited,