Even moderate consumption of ultra-processed foods increases the risk of chronic diseases

Even when consumed in moderation, ultra-processed foods are associated with a measurable increase in the risk of chronic disease, according to a study by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington. Processed meats, beverages with added sugar, and trans fatty acids (TFA) have been linked to an increased risk of diseases such as type 2 diabetes, coronary heart disease (CHD), and colorectal cancer.

Numerous studies have previously linked ultra-processed foods, especially processed meats, sugary drinks, and trans fats, to an increased risk of chronic disease. Estimates suggest that diets rich in processed meats were responsible for nearly 300,000 deaths worldwide in 2021, while diets high in sugary drinks and trans fats were responsible for millions of disability-adjusted life years lost.

Processed meats preserved by smoking, salting, or chemical additives often contain compounds such as N-nitroso agents, polycyclic aromatic hydrocarbons, and heterocyclic amines, substances that have been implicated in tumor development.

Sugary drinks remain a major source of added sugar in many populations, contributing to weight gain, cardiovascular disease, and diabetes risk. Artificial trans fats, created to harden vegetable oils, are linked to systemic inflammation and coronary heart disease.

Clarity in understanding dose-response relationships has long been limited by inconsistent data and conflicting results from different studies.

In a new study, “Health effects of processed meat, sugary beverage, and trans fat consumption: a Burden of Proof study,” published in Nature Medicine, researchers used Burden of Proof meta-regression methods to estimate the association between consumption of these foods and the risk of type 2 diabetes, coronary heart disease, and colorectal cancer.

Key findings of the study:

Processed meat

• Intakes of 0.6 g/day to 57 g/day are associated with at least an 11% higher average risk of type 2 diabetes compared with no intake.
• The relative risk (RR) of developing type 2 diabetes was estimated at 1.30 with daily consumption of 50 g.
• Consumption of 0.78 g/day to 55 g/day is associated with a 7% higher risk of colorectal cancer.
• The OR for colorectal cancer was estimated to be 1.26 at 50 g/day.
• The OR of CHD was 1.15 at 50 g/day.

Sweet drinks

• Consumption of 1.5 g/day to 390 g/day is associated with at least an 8% higher risk of type 2 diabetes.
• The OR for type 2 diabetes was estimated to be 1.20 at a consumption of 250 g/day.
• Consumption of up to 365 g/day is associated with a 2% higher risk of CHD.
• The odds ratio for CHD was estimated at 1.07 at 250 g/day.

Trans fatty acids

• Consumption of 0.25% to 2.56% of daily energy intake is associated with at least a 3% higher risk of CHD.
• The OR of CHD was estimated at 1.11 with trans fat consumption equal to 1% of daily calories.

The risk increased steadily at all levels of consumption, with the largest jumps at low habitual consumption, roughly equivalent to one serving or less per day.

Conclusions

The authors concluded that even moderate levels of consumption of these foods are associated with measurable risks and reaffirmed current public health recommendations to reduce consumption of processed meats, sugary drinks and industrial trans fats.

Given the global burden of diabetes, cardiovascular disease and colorectal cancer, the study findings support WHO initiatives including bans on industrial trans fats and taxes on sugary drinks.

Scientists have stressed that even low levels of regular consumption can pose a health risk.