Limit these ultra-processed foods for longer-term health, 30-year study suggests

New research is adding to the evidence linking ultra-processed foods to health concerns. The study tracked people's habits over 30 years and found those who reported eating more of certain ultra-processed foods had a slightly higher risk of death — with four categories of foods found to be the biggest culprits. 

For the study, published in The BMJ, researchers analyzed data on more than 100,000 U.S. adults with no history of cancer, cardiovascular disease or diabetes. Every four years between 1986 and 2018, the participants completed a detailed food questionnaire.

The data showed those who ate the most  ultra-processed food — about 7 servings per day — had a 4% higher risk of death by any cause, compared to participants who ate the lowest amount, a median of about 3 servings per day.

Ultra-processed foods include "packaged baked goods and snacks, fizzy drinks, sugary cereals, and ready-to-eat or heat products," a news release for the study noted. "They often contain colors, emulsifiers, flavors, and other additives and are typically high in energy, added sugar, saturated fat, and salt, but lack vitamins and fiber."

Foods with the strongest associations with increased mortality, according to the study, included:

• Ready-to-eat meat, poultry and seafood-based products
• Sugary drinks
• Dairy-based desserts
• Highly processed breakfast foods

Ultra-processed food is a "very mixed group of very different foods," the lead author of the study, Mingyang Song, told CBS News, meaning these categories can offer a helpful distinction. 

"Some of the foods actually have really beneficial ingredients like vitamins, minerals, so that's why we always recommend that people not focus too much on the (whole of) ultra-processed food, but rather the individual categories of ultra-processed food."

The research included a large number of participants over a long timespan, but it did have some limitations. As an observational study, no exact cause-and-effect conclusions can be drawn. And the participants were health professionals and predominantly White and non-Hispanic, "limiting the generalizability of our findings," the authors acknowledged.

But they wrote that the findings "provide support for limiting consumption of certain types of ultra-processed food for long term health." 

"Future studies are warranted to improve the classification of ultra-processed foods and confirm our findings in other populations," they added.

This study comes after other research published earlier this year found diets high in ultra-processed food are associated with an increased risk of 32 damaging health outcomes, including higher risk for cancer, major heart and lung conditions, gastrointestinal issues, obesity, type 2 diabetes, sleep issues, mental health disorders and early death.