Older adults who reported consuming greater amounts of ultra-processed foods, as defined by the American NOVA classification system, thus had a 10% increased risk of premature mortality over the 23 years of follow-up of the study.
The study follows an average of over half a million participants for nearly 30 years. The team uses several strategies to classify the level of processing of food products. This includes breaking down foods into types of food, nutrients and specific ingredients, in addition to having a group of experts classify these food components according to a recognized classification system (NOVA). Confounding factors, such as smoking and obesity, were taken into account. The analysis reveals that:
- Participants who consumed more ultra-processed foods had a higher body mass index (BMI) and a lower healthy eating index;
- higher consumption of ultra-processed foods is associated with increased deaths from all causes and deaths specifically related to heart disease or diabetes;
- however, no association was found for cancer-related deaths;
- Highly processed meat products and soft drinks are the ultra-processed food subgroups most strongly associated with mortality risk;
- These same foods are already discouraged in the vast majority of nutritional guidelines.
Lead author Erikka Loftfield, a researcher at the National Cancer Institute, notes: “The research is consistent with a body of literature of observational and experimental studies that indicate that consumption of ultra-processed foods has a negative impact on health and longevity, however we need to better identify the aspects of ultra-processed foods that lead to these health risks.”
The authors call for increased research into the relationships between food processing and human health as well than to strengthen the information provided to patients and the general public.
