Sweden study links high-fat cheese and cream to lower dementia risk

A 25-year study in Sweden found that higher daily intake of full-fat dairy products was associated with a lower risk of dementia, challenging some conventional guidance about fat consumption and brain health. The research tracked more than 27,000 Swedes who provided detailed food diaries and interviews, forming a long-running look at diet and cognitive outcomes.

Researchers recruited 27,600 healthy adults aged 45 to 73 at baseline between 1991 and 1996. Participants filled out a self-administered questionnaire on lifestyle and sociodemographic factors, kept a food diary and underwent a dietary interview at a second visit about two weeks later. Their dairy intake was categorized into high-fat and low-fat groups using standard fat-content cutoffs, and researchers calculated daily intake for each dairy product. The Swedish National Patient Registry was used to identify dementia diagnoses through the end of 2020, allowing investigators to examine whether early dietary habits influenced long-term cognitive health. By the end of follow-up, 1,920 participants had been diagnosed with dementia, including 1,126 Alzheimer's disease cases and 451 vascular dementia cases.

The analysis found a dose-dependent relationship between high-fat dairy and dementia risk. Those who consumed roughly 50 grams or more of full-fat cheese per day and about 20 grams of full-fat cream daily showed the greatest association with a lower risk of developing dementia over the following two decades. Specifically, individuals consuming approximately 1.8 ounces of full-fat cheese per day experienced about a 13 percent reduction in dementia risk compared with the group that ate the least. Meanwhile, those consuming about 1.4 tablespoons of full-fat cream daily had roughly a 16 percent lower risk. The effect extended to Alzheimer’s disease for those without the APOE ε4 gene variant, a known genetic risk factor, though the protective association with cheese did not appear in APOE ε4 carriers. The study’s authors emphasized that the findings show correlation, not causation, and did not reveal the biological mechanism behind the association.

The researchers noted that other dairy products, such as low-fat milk, yogurt, or low-fat cheese, did not demonstrate the same protective link. Dr. Emily Sonestedt of Lund University described the finding as a challenge to longstanding dietary assumptions: “For decades, the debate over high-fat versus low-fat diets has shaped health advice, sometimes even categorizing cheese as an unhealthy food to limit. Our study found that some high-fat dairy products may actually lower the risk of dementia, challenging some long-held assumptions about fat and brain health.”

Beyond dementia risk, the study observed that individuals who consumed more high-fat cheese and cream tended to have healthier overall profiles in several other areas. They generally had lower body mass index, lower rates of diabetes, reduced prevalence of high blood pressure and heart disease, and less use of cholesterol-lowering medications. Researchers suggested these broader health patterns might influence how diet relates to brain aging, though they stressed that the findings should not be used to justify high-fat dairy as a universal remedy. The authors pointed to existing dietary patterns such as the MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) diet, which emphasizes plant-based foods, whole grains, and healthy fats while limiting red meat and processed items; the new results indicate that dairy’s role within such patterns may be more complex than previously thought.

The study’s limitations include its observational design and reliance on self-reported dietary data, which can be prone to reporting biases. While the results showed a consistent association across many subgroups, they did not definitively establish why high-fat dairy might be linked to reduced dementia risk. The researchers also cautioned against interpreting the findings as an endorsement of high-fat dairy as a replacement for other healthy fats or as a universal strategy to prevent dementia. Reputable randomized trials cited in the discussion have shown that regular-fat cheese does not worsen cholesterol levels relative to low-fat cheese or no cheese, suggesting that the relationship between dairy fat and cardiovascular health may differ from its relationship with brain aging.

In sum, the Swedish study adds to a complex and evolving picture of diet and dementia risk. The association between higher intake of certain high-fat dairy products and lower dementia risk appears to be strongest for cheese and cream consumed in moderation within a broader, balanced dietary context. The authors call for further research to unravel the biological mechanisms at play and to determine how these foods fit into comprehensive dietary recommendations for aging populations. The Neurology journal published the study.