Reasons to avoid ultra-processed foods

Hundreds of epidemiological studies and meta-analyses have reported associations between ultra-processed food consumption and adverse health outcomes. In a linked paper (doi:10.1136/bmj-2023-077310), Lane and colleagues have now carefully reviewed the evidence from 45 meta-analyses encompassing almost 10 million participants.1 They found direct associations between exposure to ultra-processed foods and 32 health parameters including mortality, cancer, and mental, respiratory, cardiovascular, gastrointestinal, and metabolic ill health. For instance, a pooled analysis of seven cohorts showed a 10% increase in ultra-processed food consumption to be associated with a 12% (95% confidence interval 1.11 to 1.13) higher incidence of type 2 diabetes.

The quality of the evidence was strong for all cause mortality, obesity, and type 2 diabetes (this evidence was rated as of moderate quality using the GRADE system, which initially considers all observational studies as low quality evidence). Overall, the authors found that diets high in ultra-processed food may be harmful to most—perhaps all—body systems.

Ultra-processed foods are …