July 09,2024

Study Links Ultra-Processed Foods to Increased Mortality Risk in Older Americans

A diet high in ultra-processed foods may increase the risk of mortality among older Americans by up to 10%, according to new research.

Tracking the diet and health of over half a million participants for more than 20 years, the study found that the highest consumption of ultra-processed foods was among the younger members of the older adult cohort. The research suggests that older people consuming significant amounts of these foods were 10% more likely to die during the study period compared to those with lower consumption.

The study utilized data from the US NIH-AARP Diet and Health Study, focusing on adults aged 50 to 71 at the start in 1995-1996, with a median follow-up period of 22.9 years. Diets were scored using the NOVA system, which classifies foods based on their processing levels, and the Healthy Eating Index (HEI)-2015. Participants with higher ultra-processed food intake tended to have lower diet quality and higher BMI.

Notably, the researchers validated the food frequency questionnaires (FFQ) through expert consensus and a novel food-based approach, categorizing foods by NOVA definitions. They also used two 24-hour diet recalls in a subgroup to calibrate their FFQ risk estimates, enhancing the study's rigor.

Presented at the American Society for Nutrition's NUTRITION 2024 conference, the research highlights the health risks of ultra-processed foods, particularly their links to increased mortality from heart disease and diabetes, though not cancer.

Understanding Ultra-Processed Foods

According to the NOVA system:

Unprocessed (Natural) Foods: Directly from plants or animals without alteration.
Minimally Processed Foods: Cleaned and had inedible parts removed; may be cut, ground, dried, fermented, pasteurized, cooled, or frozen, but with no added substances.
Processed Culinary Ingredients: Extracted from natural foods (e.g., oils, fats, salt, sugar) used in small amounts.
Processed Foods: Manufactured with added sugar, salt, and oil for flavor and shelf life, with no more than two or three ingredients.
Ultra-Processed Foods (UPF): Industrial creations with ingredients like oils, fats, sugars, modified starch, and hydrogenated fats, along with colorings and flavor enhancers, often containing five or more ingredients.
Significance of the Study

The study stands out due to its large sample size—318,889 men and 221,607 women—and its extended follow-up period. Dietitian Kristin Kirkpatrick, MS, RDN, noted the lengthy follow-up was significant but mentioned that details on dietary changes or other health-risk activities during the period were unclear.

Michelle Routhenstein, MS, RD, CDCES, pointed out that the study shows higher consumption of ultra-processed foods increases mortality risk, independent of factors like smoking, obesity, and diet quality. Ultra-processed foods, higher in added sugars, unhealthy fats, and additives, lack essential nutrients and contain advanced glycation end products (AGEs), which can increase oxidative stress, inflammation, and cardiovascular disease risk.