Full-Fat Dairy Linked to Lower Dementia Risk: A 25-Year Study

A new study published in December 17, 2025, in Neurology suggests a potential link between regular consumption of high-fat cheese and cream and a reduced risk of dementia. The 25-year prospective cohort study, involving over 27,670 Swedish adults, challenges long-held dietary advice favoring low-fat dairy products.

Researchers followed participants from 1991 to 1996 for dietary assessment, utilizing a combination of 7-day food diaries, food frequency questionnaires and dietary interviews. Dementia cases were then identified through the Swedish National Patient Register up to December 31, 2020, with diagnoses up to 2014 undergoing further validation. During a median follow-up of 25 years, 3,208 incident dementia cases were recorded.

The study found that consuming ≥50 g/d of high-fat cheese (defined as >20% fat) was associated with a reduced risk of all-cause dementia (hazard ratio 0.87; 95% confidence interval, 0.78-0.97) compared to lower intake (<15 g/d). A similar association was observed for vascular dementia (HR 0.71, 95% CI 0.52-0.96). Among individuals without the APOE ε4 gene, higher consumption of high-fat cheese was also linked to a lower risk of Alzheimer’s disease (HR 0.87, 95% CI 0.76-0.99, p-interaction = 0.014).

individuals consuming ≥20 g/d of high-fat cream (>30% fat) had a 16% lower risk of all-cause dementia (HR 0.84, 95% CI 0.72-0.98) compared to those consuming none. This inverse association extended to both Alzheimer’s disease and vascular dementia.

However, the findings have prompted some caution from experts. Walter Willett, professor of epidemiology and nutrition at Harvard T.H. Chan School of Public Health, noted that the association for cheese was “at the margin of statistical significance,” and that observing multiple foods increases the chance of finding results due to chance. Other concerns raised include the reliance on dietary data collected primarily at the beginning of the study period and the possibility that the benefits observed were due to participants replacing red and processed meat with high-fat dairy.

Study author Emily Sonestedt, PhD, of Lund University, Sweden, acknowledged the long-held assumptions about fat and brain health, stating, “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.”

Researchers suggest the benefits may not be solely attributable to fat content. High-fat cheese provides a range of nutrients including proteins, essential amino acids, vitamins K2 and E, selenium, compounds resulting from fermentation, and probiotics, all of which may contribute to brain health. The study also notes a potential indirect effect, as high-fat cheese consumption has been previously linked to a lower risk of type 2 diabetes and hypertension – conditions frequently associated with cognitive decline.

It’s important to note the study’s limitations. Alexis Wood, associate professor of nutrition at Baylor College of Medicine, described the analysis as “one of the most robust in nutritional epidemiology” due to its large sample size and long follow-up period, but emphasized that the results remain observational. “We don’t know why some participants chose higher-fat dairy products and others chose lower-fat options, and it’s possible that people who consumed more high-fat cheese also had other protective factors, including different social contexts,” she explained.

Additional limitations include the fact that the data primarily comes from the 1990s, the study was conducted exclusively in Sweden, dietary information was self-reported, and other relevant dietary factors were not fully controlled for in the analysis. These factors necessitate cautious interpretation of the results.

Despite these limitations, researchers emphasize that the study provides valuable information, but does not yet provide sufficient evidence to support significant dietary changes based solely on these findings. The authors concur, stating that evidence remains premature for firm recommendations.

The research team notes that moderate cheese consumption, as part of a balanced diet, does not appear to be harmful and may be associated with certain benefits. A separate study by the same researchers indicated an association between higher high-fat cheese intake and a lower risk of overall mortality.

However, for individuals with cardiovascular disease or risk factors, current recommendations to limit saturated fat intake, as outlined by the World Health Organization and American Heart Association, remain in effect.

Currently, the U.S. Department of Agriculture’s Dietary Guidelines emphasize a diet rich in fruits, vegetables, whole grains, lean proteins, and healthy fats, while limiting foods high in sugar, saturated fat, alcohol, and sodium. Alexis Wood recommends adhering to these guidelines, stating, “This approach reduces the risk of chronic diseases associated with aging and supports heart and metabolic health, which, in turn, supports brain health as you get older.”

Beyond dietary choices, factors such as physical activity, social connections, regular medical check-ups, and stress management also play crucial roles in maintaining overall health and cognitive function. No single food, regardless of study findings, can replace these comprehensive lifestyle factors.

Researchers plan to conduct further studies, including controlled clinical trials, to confirm these findings in diverse populations and to determine the specific components of cheese responsible for the observed effects and optimal dosages. Only then can evidence-based recommendations be formulated.

In short, cheese does not need to be automatically eliminated from the diet, nor should it be considered a guaranteed solution for dementia prevention. A diverse diet, moderation, and a healthy lifestyle remain the most reliable long-term investments in health.