People who regularly ate higher-fat cheese and cream had a lower risk of developing dementia over 25 years, while low-fat dairy and other milk products showed no clear benefit, according to a new study published in Neurology. The research followed nearly 28,000 people in Sweden and tracked their diets and brain health over time.
Those who consumed 50 grams or more of high-fat cheese a day — roughly a third of a cup — had a lower overall risk of dementia and of vascular dementia, a type of cognitive decline caused by reduced blood flow to the brain. People who averaged at least 20 grams of high-fat cream daily, about one and a half tablespoons, also showed a lower risk of dementia in the study.
By contrast, low-fat cheese, low-fat cream, and butter were not associated with lower dementia risk. Milk intake, whether high- or low-fat, also did not appear to reduce dementia risk.
Why might high-fat cheese and cream help when milk doesn’t?
Lead author Emily Sonestedt, an associate professor at Lund University, said the most likely explanation is that different dairy products play very different roles in people’s diets — and bring different biology with them.
“Cheese is fermented, which produces bioactive compounds that may influence inflammation and blood vessels. Cream is usually used in home-cooked meals, not consumed in large quantities on its own,” Sonestedt told media, “Milk intake, on the other hand, varies more across diet patterns and doesn’t have the same fermentation process.”
Fermented foods like cheese contain a mix of peptides, fats, and microbial byproducts that can affect blood pressure, blood vessels, and possibly the brain. Other research has suggested that some cheeses, especially fermented varieties, may influence brain pathways related to inflammation and neuroprotection, but the science is still developing.
Not all dairy — or cheese — is created equal
The source and quality of dairy may also matter, said Dr. Richard Isaacson, a neurologist who specializes in dementia prevention at the Institute for Neurodegenerative Disease.
“Not all cheese is created equal,” Isaacson said. “What a cow eats determines what’s in the milk — and that determines what’s in the cheese.” He noted that dairy from grass-fed cows, especially those that graze throughout their lives, typically contains higher levels of omega-3 fatty acids, which are known to be protective for the brain.
“Omega-3 fatty acids are preferentially protective for the brain,” he added, particularly for people already at risk of cognitive decline.
That means a wedge of aged, grass-fed cheese enjoyed as part of an overall balanced diet is very different from ultra-processed cheese slices in a fast-food burger. The study’s broad category of “high-fat cheese” does not capture those nuances, but experts say quality is likely to matter in real-world eating patterns.
Genetics and the APOE ε4 gene change the picture
One of the most striking findings in the study is that people who carry the APOE ε4 genetic variant — a major inherited risk factor for Alzheimer’s disease — did not see the same benefit from high-fat dairy as those without the gene.
Roughly 15–20% of people carry at least one copy of APOE ε4. For them, the Swedish researchers found no clear reduction in dementia risk from any type of dairy intake.
“The fact that we saw a clearer association with vascular dementia, and with Alzheimer’s only in people without the APOE ε4 variant, suggests that the pathway may be more related to vascular and metabolic factors than to the core amyloid processes,” Sonestedt said.
Isaacson said the finding reinforces the idea that dietary advice may need to be personalized, especially when it comes to saturated fat.
“People who carry the APOE ε4 gene are more sensitive to saturated fat than people who don’t,” he said. While some people may tolerate moderate amounts of saturated fat without obvious harm, others — especially those with high genetic risk for dementia — may need to be far more cautious.
“There is no one-size-fits-all approach to Alzheimer’s prevention,” Isaacson stressed.
This isn’t proof that cheese prevents dementia
Despite the headline-friendly results, the authors are clear: the study does not prove that eating high-fat cheese and cream prevents dementia.
“It’s an observational study. Cheese and cream may simply be markers of broader eating patterns and lifestyle factors. This is not a green light to dramatically increase intake,” Sonestedt said.
People who eat more full-fat cheese and cream might, for example, have different levels of education, physical activity, income, or medical care than those who avoid them — all factors that can influence dementia risk. Even though the researchers adjusted for many of these differences, unmeasured lifestyle habits could still explain some or all of the association.
Experts say the safest takeaway is that moderate amounts of high-quality, full-fat cheese or cream, especially as part of home-cooked meals and an overall healthy diet, don’t appear to harm brain health and may even be neutral or slightly beneficial for many people.
Dementia is rising — and diet is only one piece of prevention
The stakes are high. An estimated 6.7 million Americans aged 65 and older are living with Alzheimer’s dementia today, a number expected to more than double by around 2050–2060 as the population ages.
Against that backdrop, studies like this one add to a growing body of evidence that long-term habits — including diet, exercise, sleep, blood pressure control and social engagement — can nudge dementia risk up or down over decades.
“I wouldn’t recommend major diet changes based on one study,” Sonestedt said. “But people who enjoy cheese or use cream in cooking don’t need to feel concerned about these foods in moderate amounts.”
For now, the high-fat cheese dementia risk study offers both a bit of reassurance for cheese lovers and a reminder that brain-healthy eating is likely to be nuanced and individualized — less about cutting out a single food group and more about the overall pattern on your plate.
Sources:
The Times – “Could full-fat cheese and cream protect against dementia?”
