Ultra-processed foods are everywhere. They include many packaged snacks, sugary drinks, instant noodles, processed meats, sweet breakfast cereals, ready-made meals, and many foods made with ingredients that are rarely used in home cooking.
These products are often convenient, inexpensive, and have a long shelf life. Because they are so common, many people eat them every day without thinking much about how they may affect long-term health.
Scientists have become increasingly interested in ultra-processed foods because many studies have linked high intake with obesity, type 2 diabetes, heart disease, several cancers, and a greater risk of early death.
However, researchers have not fully understood why these foods appear to be linked with poorer health. A new international study has provided another important clue by looking at what happens inside the body after people regularly eat more ultra-processed foods.
The research was led by Dr. Jessica Blanco-Lopez from the International Agency for Research on Cancer, which is part of the World Health Organization. The findings were published in Critical Reviews in Food Science and Nutrition.
The study examined information from 15,200 adults who took part in the large European Prospective Investigation into Cancer and Nutrition, often called the EPIC study.
The researchers first collected detailed information about what the participants usually ate. They grouped foods using the NOVA classification system, which sorts foods according to how much industrial processing they have gone through. F
resh fruit, vegetables, milk, eggs, and grains are considered minimally processed, while foods containing many industrial ingredients, additives, preservatives, flavorings, or colorings are usually placed in the ultra-processed group.
The team also collected blood samples. Instead of simply measuring cholesterol or blood sugar, they looked at hundreds of tiny chemicals called metabolites.
Metabolites are produced as the body digests food, creates energy, repairs cells, and carries out thousands of normal processes every day. By measuring these chemicals, scientists can better understand how the body responds to different eating patterns.
After carefully analyzing the results and accounting for age, lifestyle, and other health factors, the researchers found that people who ate more ultra-processed foods had a distinct pattern of chemicals in their blood.
Twenty-two different metabolites were linked with greater intake of these foods. Many of these changes suggested that the body was under greater metabolic stress and was not handling fats in the healthiest way.
The researchers also found changes in eight different fatty acids. Some fatty acids that normally help maintain healthy cell membranes were lower, while other fatty acids associated with saturated fat intake and altered metabolism were higher.
The results suggest that ultra-processed foods may influence the body’s own production and handling of fats instead of simply reflecting the fat already present in the diet. This means foods rich in refined carbohydrates and industrial ingredients may encourage the body to produce extra fats internally.
These findings may help explain why people who regularly eat large amounts of ultra-processed foods often have a higher risk of chronic diseases. The study does not prove that these foods directly caused the blood changes because it measured people at one point in time.
It shows an association rather than cause and effect. Even so, the researchers tested several analytical methods and found very similar results each time, increasing confidence in the reliability of the findings.
Overall, this research strengthens the growing evidence that diets based mainly on fresh and minimally processed foods are likely to be healthier than diets dominated by ultra-processed products. Future long-term studies will be needed to determine exactly how these blood changes contribute to disease.
For now, the results support advice to limit ultra-processed foods and replace them with fruits, vegetables, whole grains, beans, nuts, fish, and other less processed choices whenever possible.
The study provides strong evidence that ultra-processed foods leave measurable biological changes in the body. Although it cannot prove these foods directly cause disease, the consistency of the results and the large number of participants make the findings convincing.
Future research following people over many years will be important to determine whether these metabolic changes are the first steps leading to chronic illness.
If you care about health, please read studies that vitamin D can help reduce inflammation, and vitamin K could lower your heart disease risk by a third.
For more health information, please see recent studies about new way to halt excessive inflammation, and results showing foods that could cause inflammation.
Source: International Agency for Research on Cancer (IARC/WHO).
