Every additional 100 grams of ultra-processed food eaten per day is linked to higher risks of cardiovascular disease, cancer and diabetes, according to an international study. The research confirmed the association between ultra-processed food intake and health risks on a large scale.
An international team led by Dr. Xiao Liu of Duke-NUS Medical School in Singapore published the meta-analysis on the 23rd in the journal Family Medicine and Community Health. The researchers pooled and analyzed 51 prospective cohort studies published through April. By region, 16 were from the Americas, 25 from Europe, eight from Asia and two from Oceania. The studies covered 8,819,894 people, with mean ages ranging from 23 to 77 and follow-up periods of two to 32 years. The team conducted the analysis to identify the dose-response relationship between ultra-processed food intake and the onset of chronic disease.
Ultra-processed foods are products made through industrial processing so they can be eaten immediately or after heating. They contain multiple food additives and are high in calories, sugar and sodium, while containing relatively little dietary fiber, protein, vitamins and minerals.
The analysis found that the group consuming the most ultra-processed food had a 24% higher risk of cardiovascular disease than the group consuming the least. Cancer risk was 12% higher, the risk of being overweight or obese 23% higher, and the risk of metabolic syndrome and diabetes 24% higher. The risk of depression and anxiety was 27% higher, digestive disease 31% higher and hypertension 11% higher, while the risk of death from all causes was 18% higher. The mortality analysis drew on nine studies covering about 400,000 people.
A dose-response relationship between intake and risk was also confirmed. For each additional 100 grams consumed per day, the risk of cardiovascular disease rose 14%, cancer 4%, death 3% and metabolic syndrome and diabetes 2%. These figures do not mean an individual's disease risk climbs by that amount when they eat an extra 100 grams of ultra-processed food. They are values calculated by combining the associations between intake and incidence found across multiple studies.
The researchers pointed to the combined effects of food additives and changes in the physical structure of food during processing as pathways through which ultra-processed foods affect health. Consuming multiple additives together can produce what is known as a cocktail effect, they said. They added that substances such as acrylamide and acrolein, which form during heating at high temperatures or during processing, were also found to be linked to increased cardiovascular disease risk.
The study has limitations. Many of the included studies used subjective dietary assessment methods such as food frequency questionnaires or 24-hour dietary recall. People under 18 were excluded from the analysis. Another limitation is that ultra-processed food consumption often occurs alongside other lifestyle factors such as smoking, physical activity and overall eating habits, making it difficult to isolate the effect of ultra-processed foods alone. The researchers added that future work needs to break down food categories in more detail and standardize methods for measuring ultra-processed food intake.
"Chronic diseases associated with ultra-processed food consumption often appear as multiple conditions at the same time," Liu said. "To prevent and manage chronic disease, it is worth considering reducing ultra-processed food intake and replacing it with minimally processed foods."
