Expert comment: link between 'ultra-processed' foods and heart disease29 May 2019
Dr Gunter Kuhnle, Associate Professor in Nutrition and Health, University of Reading, said:
“These are two very well and thoroughly conducted studies which show that very high intake of ‘ultra-processed’ foods are associated with higher disease risk. Increases in cardio-vascular disease risk were rather modest and only found in people whose diet included more than 30% ultra-processed foods (less than a quarter of the study population) – however no increases in death from heart disease or cancer were found. Indeed, increased mortality was only observed in those consuming four or more servings of ‘ultra-processed’ food per day.
“These studies are important, as they show that there is an association between the consumption of ‘ultra-processed’ foods and health which warrants further investigation. A study published previously suggests that these foods encourage overeating, and ‘hyperpalatabilty’ of many – but not all – foods in the ‘ultra-processed’ category could explain to some extent the observed associations.
“The one major limitation of these studies is the focus on ‘ultra-processed’ foods. While the term is convenient to create the image of ‘unhealthy food’, it is neither specific nor useful to inform public health or give dietary advice. While ‘ultra-processed’ food is commonly assumed to be food that is extensively processed and where “numerically the majority of ingredients are preservatives; stabilizers, emulsifiers, solvents, binders, bulkers; sweeteners, sensory enhancers, colors and flavors; processing aids and other additives” (from the NOVA classification, https://link.springer.com/article/10.1007/s13679-014-0092-0), it actually contains foods which undergo few processing steps, such as hamburgers, crisps or chips, or contain preservatives that have been used for centuries such as preserves. It is also not obvious why salami is considered to be ultra-processed, yet cheese, which often requires considerably more processing steps and additives, is not. The classification combines a wide range of foods with very different potential impacts on health, which limits its usefulness as a basis for recommendations.
“It is likely that the consumption of ultra-processed foods is a marker for an overall ‘unhealthy’ lifestyle. Indeed, it is noticeable that the population with the highest intake of ‘ultra-processed’ food had a generally rather unhealthy lifestyle and was more likely to smoke and less likely to be physically active. Dealing with these underlying causes is more important than simply addressing the symptoms.”