The world's largest review of its kind has found that ultra-processed foods (UPFs) are directly linked to 32 harmful effects on health, including increased risks of heart disease, cancer, type 2 diabetes, mental health issues, and early death. The comprehensive umbrella review, published in the BMJ, analysed 45 pooled meta-analyses from 14 review articles involving nearly 10 million people.
In the UK and US, UPFs now make up more than half of the average diet, with some younger, poorer, or disadvantaged individuals consuming up to 80%. These foods, which include fizzy drinks, ready meals, sugary cereals, and packaged snacks, undergo multiple industrial processes and contain additives such as colours, emulsifiers, and flavours, while being high in added sugar, fat, and salt but low in vitamins and fibre.
The review found convincing evidence that higher UPF intake is associated with a 50% increased risk of cardiovascular disease-related death, a 48-53% higher risk of anxiety and common mental disorders, and a 12% greater risk of type 2 diabetes. Highly suggestive evidence also linked UPFs to a 21% increased risk of death from any cause, a 40-66% higher risk of heart disease-related death, obesity, type 2 diabetes, sleep problems, and a 22% increased risk of depression.
Additional associations were found with asthma, gastrointestinal issues, some cancers, and cardiometabolic risk factors like high blood fats and low 'good' cholesterol, though the evidence for these was limited. The researchers, from institutions including Johns Hopkins University, the University of Sydney, and Sorbonne University, called for population-based measures to reduce UPF exposure. None of the included studies were funded by UPF producers.
Experts noted limitations, including potential unmeasured factors and variations in assessing UPF intake, and highlighted that much of the underlying research was weak. Nevertheless, the findings underscore the urgent need for public health interventions to curb consumption of ultra-processed foods.
