Ultra-processed foods increase the risk of death. This is revealed by a study conducted over 30 years in the United States, published in
The BMJ. Ready-to-eat products made from meat, poultry, seafood, sugary drinks, dairy desserts, and breakfast foods are the most affected.
Ultra-processed foods include ready-to-eat products, sodas, sugary cereals, packaged bakery products, and snacks. They often contain colorings, emulsifiers, flavors, and other additives, and are high in energy, added sugar, saturated fats, and salt, but low in vitamins and fiber.
Evidence is mounting on the increased risks of obesity, heart disease, diabetes, and colorectal cancer associated with these foods. However, few studies have examined long-term links with all-cause and specific-cause deaths.
Researchers followed the health of 74,563 nurses and 39,501 male health professionals without a history of cancer, cardiovascular disease, or diabetes. Participants provided information about their health and lifestyle every two years, and a detailed food questionnaire every four years. Overall diet quality was assessed via the AHEI-2010 score.
Over an average follow-up of 34 years, researchers identified 48,193 deaths, including 13,557 from cancer, 11,416 from cardiovascular diseases, 3,926 from respiratory diseases, and 6,343 from neurodegenerative diseases.
Compared to participants consuming the fewest ultra-processed foods (3 servings per day on average), those consuming the most (7 servings per day on average) had an increased risk of total death by 4%, and an increased risk of neurodegenerative death by 8%.
The associations between ultra-processed food consumption and mortality varied by food group. Meat, poultry, and seafood-based products were most strongly associated, followed by sugary drinks and dairy desserts.
The association was less pronounced when considering overall diet quality, suggesting that the latter has a greater influence on long-term health.
This study is observational and does not allow for definitive conclusions on causality. The authors emphasize that the classification of ultra-processed foods does not capture all the complexity of food processing, leading to possible misclassification. Also, since the participants were health professionals, generalization of the results is limited.
Researchers insist that not all ultra-processed foods should be universally restricted and advise against overly simplifying dietary recommendations.