Not all ultra-processed foods are created equal: a review

The Nova system was proposed as a means of categorising food products according to the degree and methods of processing. The term 'ultra-processed' was used to indicate foods with the most extensive processing. When applied to research cohorts, foods in this category have shown widely heterogeneous associations with diabetes, cardiovascular disease and other chronic conditions, with some foods associated with increased risk and others associated with significantly reduced risk, raising important considerations for public policy. The purpose of this review is to summarise the findings of studies analysing the associations of ultra-processed foods with the risk of cardiometabolic diseases. Out of 309 records found on PubMed, 14 publications that differentiated between ultra-processed food groups were included in the review. Positive associations between ultra-processed food consumption and adverse health outcomes have been found for processed meats, sweetened beverages (both sugar-sweetened and artificially sweetened), and fats, spreads and sauces. Other ultra-processed foods have been associated with lower risk of these conditions, mainly breads, biscuits and breakfast cereals, and whole grains. Randomised clinical trials show that replacing animal products with plant-based foods, even when processed, leads to health benefits. These studies suggest that the Nova system may be improved by differentiating between animal and plant foods.