The foods that delay dementia and heart disease. Backed by a 15-year study

A healthy diet can slow down the accumulation of chronic diseases in older adults, while inflammatory diets accelerate it. This is shown by a new study from Karolinska Institutet published in Nature Aging.

Researchers have investigated how four different diets affect the accumulation of chronic diseases in older adults. Three of the diets studied were healthy and focused on the intake of vegetables, fruit, whole grains, nuts, legumes, unsaturated fats and reduced intake of sweets, red meat, processed meat and butter/margarine. The fourth diet, however, was pro-inflammatory and focused on red and processed meat, refined grains and sweetened beverages, with lower intake of vegetables, tea and coffee.

Just over 2,400 older adults in Sweden were followed for 15 years. The researchers discovered that those who followed the healthy diets had a slower development of chronic diseases. This applied to cardiovascular disease and dementia, but not to diseases related to muscles and bones. Those who followed the pro-inflammatory diet, on the other hand, increased their risk of chronic diseases.

“Our results show how important diet is in influencing the development of multimorbidity in aging populations,” says co-first author Adrián Carballo-Casla, postdoctoral researcher at the Aging Research Centre, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet.

The next step in their research is to identify the dietary recommendations that may have the greatest impact on longevity and the groups of older adults who may benefit most from them, based on their age, gender, psychosocial background and chronic diseases.

The study was funded by the Swedish Research Council (VR) and the Swedish Research Council for Health, Working Life and Welfare, FORTE, among others. The researchers state that there are no conflicts of interest.

Facts about the diets:

MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay): A diet designed for brain health and to reduce the risk of dementia.

AHEI (Alternative Healthy Eating Index): A diet that measures adherence to dietary guidelines that reduce the risk of chronic diseases in general.

AMED (Alternative Mediterranean Diet): A modified version of the Mediterranean diet adapted to Western eating habits.

EDII (Empirical Dietary Inflammatory Index): An index that estimates the inflammatory risks of a diet.

Source: https://sciencedaily.com/releases/2025/09/250909031513.htm

Journal article: https://www.nature.com/articles/s43587-025-00929-8  

Source: The foods that delay dementia and heart disease. Backed by a 15-year study – Scents of Science