Evidence is mounting about the harms of processed foods in particular. A 30-year-old study in the United States found that a higher consumption of highly processed foods is associated with a higher risk of premature death. The strongest associations were seen with meat, poultry, and seafood products, as well as sweetened beverages, dairy desserts, and highly processed breakfast foods (ie, cereal).
The results of the study were published this week in the scientific journal BMJ.
The researchers say that not all highly processed foods should be restricted universally, but their findings “support that the consumption of certain highly processed foods should be limited to ensure long-term health.”
A link with the risk of early death was discovered
Highly processed foods include ready-to-eat baked goods and snacks, carbonated beverages, sugary cereals and heat-treated products. They often contain dyes, emulsifiers, fragrances and other additives. This food is also high in calories, high in added sugar, saturated fat, and salt, but lacks vitamins and fiber.
There is mounting evidence that highly processed foods are linked to higher risks of obesity, heart disease, diabetes and bowel cancer, but until now there have not been many long-term studies that have looked at associations with all-cause and cause-specific death, particularly from cancer.
To fill gaps in existing knowledge, researchers followed 74,563 female registered nurses from 11 US states who participated in the Nurses’ Health Study (1984-2018) and 39,501 male health care professionals from all 50 US states who participated in the Health Care Professional Follow-up Study (1986-2018).
All participants were free of cancer, cardiovascular disease or diabetes at baseline.
Participants provided information about their health and lifestyle habits every two years, and completed a detailed nutritional questionnaire every four years. Overall diet quality was also assessed using Alternative Healthy Eating Index-2010 (AHEI) scores.
During a median follow-up of 34 years, the researchers identified 48,193 deaths, including 13,557 deaths from cancer, 11,416 deaths from cardiovascular disease, 3,926 from respiratory disease, and 6,343 from neurodegenerative diseases.
Compared to participants with the lowest intake of highly processed foods (average of 3 servings per day), participants with the highest intake (average of 7 servings per day) were found to have a 4 percent higher risk of death.
However, no link has been established for deaths from cardiovascular disease, cancer, or respiratory disease.
The association between consumption of highly processed foods and death varied by food group, with the strongest association for pre-prepared meat, poultry and seafood, followed by drinks sweetened with sugar and artificial sweeteners, dairy desserts and highly processed breakfast foods.
However, the overall quality of the diet has been found to have a greater impact on long-term health than the consumption of highly processed foods, the authors note.
This is an observational study, so no firm conclusions can be drawn about cause and effect, and the authors note that the classification system for highly processed foods does not reflect the complexity of the entire food processing process, so food classification may not be entirely accurate.
However, the scope and duration of the study are its advantages. Extensive repeated measures were used, and the results were similar after further analyses, lending credibility to the researchers’ findings.
“The findings support the need to limit consumption of certain types of highly processed foods for long-term health,” the researchers write.
Prepared by MedicalXpress inf.
