A 25-year Swedish study found that people who ate full-fat cheese and did not carry a genetic risk for Alzheimer’s disease were 13% to 17% less likely to develop the condition.

According to Science Daily, researchers followed nearly 25,000 participants, of whom 3,208 developed Alzheimer’s disease over the study period. Those with genetic factors that predisposed them to Alzheimer’s did not appear to benefit from eating full-fat cheese, the researchers noted.

The unexpected link between fat and cognitive protection also extended to people who consumed more than 20 grams of full-fat cream per day. These individuals had a 16% to 24% lower risk of developing Alzheimer’s disease, according to the study published in Neurology. No similar benefit was seen in people who consumed low-fat or high-fat milk, fermented or non-fermented milk, or low-fat cream.

These findings align with earlier research showing that cheese consumption may lower the risk of heart disease and that full-fat dairy does not increase the risk of cardiovascular disease. Because heart disease and dementia share many of the same underlying risk factors — including high blood pressure, diabetes, and obesity — the results appear biologically plausible.

Still, the findings challenge long-standing nutritional advice that has traditionally favored low-fat dairy for heart health.

While results from studies in other populations have been mixed, a Finnish study that followed middle-aged men for 22 years also found that cheese consumption was associated with a 28% reduction in dementia risk.

The Swedish researchers took care to screen participants for early signs of cognitive decline. They also noted that some of the apparent benefits of eating full-fat cheese and cream were seen in people who had replaced red or processed meat with these dairy foods.

Experts caution, however, that individual foods should not be viewed in isolation when it comes to reducing dementia risk. Overall dietary patterns matter more. For example, the widely studied Mediterranean diet — associated with lower risks of both dementia and heart disease — includes moderate amounts of cheese along with vegetables, fish, whole grains, and fruit.

Researchers also observed that participants who consumed more full-fat cheese and cream tended to be more educated, were more likely to have a healthy weight, and had lower rates of other dementia-related risk factors such as heart disease, stroke, high blood pressure, and diabetes.

Full-fat cheese contains several nutrients that support brain health, including fat-soluble vitamins A, D, and K2, as well as vitamin B12, folate, iodine, zinc, and selenium. Still, experts emphasize that the findings do not justify eating large amounts of full-fat foods in an effort to prevent dementia. The consistent recommendation remains to eat a balanced diet in moderation and follow proven lifestyle habits that promote overall health and longevity.