Quick Facts

• People eating 50+ grams of high-fat cheese daily showed 13-17% lower dementia risk over 25 years
• Full-fat cream consumption above 20 grams daily linked to 16-24% reduced dementia risk
• No protective effects found for low-fat dairy products, milk, or butter

A 25-year study of 27,670 Swedish adults has found that eating high-fat cheese and cream may reduce the risk of developing dementia. The research, published in Neurology in January 2026, challenges long-held assumptions about saturated fat and brain health.

Participants who consumed more than 50 grams of high-fat cheese daily (containing over 20% fat) showed a 13% to 17% lower risk of developing Alzheimer’s disease. Those eating more than 20 grams of high-fat cream daily (over 30% fat) had a 16% to 24% lower dementia risk compared to non-consumers.

“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,” said lead researcher Emily Sonestedt of Lund University, Sweden. “Our study found that some high-fat dairy products may actually lower the risk of dementia.”

The study followed participants with an average age of 58 for approximately 25 years. During this period, 3,208 people developed dementia. Researchers found no protective effects from low-fat dairy products, milk of any fat content, butter, or fermented milk products like yogurt.

The benefits appeared strongest for vascular dementia and Alzheimer’s disease in people without the APOE ε4 genetic variant. People carrying this gene variant are more sensitive to saturated fat, according to neurologist Dr. Richard Isaacson.

“Cheese is fermented, which produces bioactive compounds that may influence inflammation and blood vessels,” Sonestedt explained to ABC News. The fermentation process may create beneficial compounds not found in other dairy products.

One potential mechanism involves pentadecanoic acid (C15:0), an odd-chain fatty acid found primarily in dairy fat. This compound activates longevity pathways and is higher in people living in Blue Zones, regions known for exceptional longevity.

The findings come as dementia cases are projected to triple by 2050, rising from 57 million in 2019 to 153 million cases worldwide. The functional dairy market is expected to more than double by 2034, reaching $45.1 billion.

Researchers caution against dramatic dietary changes based on these results. “This does not prove that cheese prevents dementia,” Sonestedt told USA Today. “Cheese and cream may simply be markers of broader eating patterns and lifestyle factors.”

The study’s limitations include its focus on Swedish participants, whose dietary habits may differ from other populations. In Sweden, cheese is often eaten uncooked, while Americans frequently consume it heated or with meat.

“There is no one-size-fits-all approach to Alzheimer’s prevention,” Isaacson stressed, noting that genetic factors significantly influence how individuals respond to saturated fat intake.

Read more: Eating More of This Dairy Product May Reduce Your Risk of Dementia