For decades, nutrition advice has often favored low-fat dairy, especially for long-term health. A new study suggests the relationship between dairy fat and brain health may be more complicated than once thought.
Researchers analyzing dietary data from nearly 28,000 adults in Sweden found that people who regularly consumed higher amounts of high-fat cheese and cream were less likely to develop dementia over time. The findings were published in Neurology, the medical journal of the American Academy of Neurology, and are based on dietary patterns tracked over an average of 25 years.
Participants were an average age of 58 when the study began. During follow-up, more than 3,200 people developed dementia. Researchers compared dementia risk among people with different levels of dairy intake, adjusting for factors such as age, sex, education and overall diet quality.
Those who ate at least 50 grams of high-fat cheese per day had a 13% lower risk of developing dementia compared with those who ate less than 15 grams daily. High-fat cheeses were defined as those containing more than 20% fat and included varieties such as cheddar, Brie and Gouda. When researchers looked specifically at vascular dementia, higher cheese intake was associated with a 29% lower risk.
A similar pattern was seen with cream. People who consumed 20 grams or more of high-fat cream per day had a 16% lower risk of dementia compared with people who consumed none. No associations were found for low-fat cheese, low-fat cream, milk, butter or fermented dairy products such as yogurt and kefir.
“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,” said Emily Sonestedt, PhD, of Lund University in Sweden.
The study also explored whether genetics played a role. Higher cheese intake was linked to a lower risk of Alzheimer’s disease only among participants who did not carry the APOE e4 gene variant, a known genetic risk factor for Alzheimer’s. Among carriers of the variant, the association was not observed.
Importantly, the researchers emphasize that the study does not prove high-fat dairy protects against dementia. Participants reported their food intake over a limited period, and dietary habits tend to cluster with other lifestyle factors that may influence brain health. People who eat more cheese may differ in meaningful ways from those who eat very little, beyond dairy choices alone.
The findings may also reflect cultural differences in how dairy is consumed. In Sweden, cheese is often eaten uncooked and as part of meals that differ from typical U.S. eating patterns, where cheese is frequently paired with processed meats or used in highly processed foods. The researchers note that similar studies in other populations are needed to see whether the results hold elsewhere.
“These findings suggest that when it comes to brain health not all dairy is equal,” Sonestedt said. “More research is needed to confirm our study results and further explore whether consuming certain high-fat dairy truly offers some level of protection for the brain.”
For now, the study adds to a growing body of research suggesting that the health effects of foods like cheese may depend on context, quantity and overall dietary patterns, rather than fat content alone.
The study was supported by the Swedish Research Council, the Swedish Heart and Lung Foundation, the Crafoord Foundation, the Magnus Bergvall Foundation and the Albert Påhlsson Foundation.