A recent study found that older adults who eat a lot of ultra-processed foods are almost 10% more likely to die over a period of 23 years compared to those who eat less of these foods. This study followed over 500,000 people in the United States for about 30 years. The findings show a slight increase in deaths from heart disease and diabetes, as well as overall deaths, linked to higher consumption of ultra-processed foods. However, no link was found between these foods and cancer deaths.
“Our study results support a larger body of literature, including both observational and experimental studies, which indicate that ultra-processed food intake adversely impacts health and longevity,” said Erikka Loftfield, PhD, Stadtman Investigator at the National Cancer Institute. “However, there is still a lot that we don’t know, including what aspects of ultra-processed foods pose potential health risks.”
Loftfield will present the findings at NUTRITION 2024, the annual meeting of the American Society for Nutrition, held from 29th June to 2nd July in Chicago.
The study collected data from over 540,000 people who shared details about their eating habits and health in the mid-1990s when they were between 50 and 71 years old. More than half of these participants have since died. The researchers compared death rates among those who were in the top 10% for eating ultra-processed foods with those in the bottom 10%. They also looked at the links between specific foods and diseases.
“We observed that highly processed meat and soft drinks were a couple of the subgroups of ultra-processed food most strongly associated with mortality risk, and eating a diet low in these foods is already recommended for disease prevention and health promotion,” said Loftfield. The Dietary Guidelines for Americans recommend limiting sugar-sweetened beverages and processed meats like hot dogs, sausages, and deli meat.
To classify the level of processing for different foods, the researchers used several methods. They broke down food frequency questionnaire data into specific food and ingredient types and used expert opinions to categorize dietary components according to a system known as the NOVA classification.
The researchers also considered other factors that can increase the risk of death, such as smoking and obesity. They found that people who ate more ultra-processed foods also tended to have a higher body mass index and a lower Healthy Eating Index score, which measures how well a person’s diet aligns with the Dietary Guidelines for Americans.
However, the analysis showed that the links between eating more ultra-processed foods and higher death rates were not explained by these factors. The associations persisted among people with both good and poor diet quality, as well as among those who were of normal weight or obese.
This study suggests that eating more ultra-processed foods may increase the risk of death, especially from heart disease and diabetes. While it supports the idea that these foods are bad for health, there is still much to learn about why they are harmful. Limiting processed meats and sugary drinks, as recommended by dietary guidelines, could help reduce this risk.