Previous research has shown that a diet high in saturated and trans fats is a no-no for maintaining a healthy heart. Now a new study from Brigham and Women’s Hospital (BWH) goes further, finding these same “bad” fats are associated with poor cognitive function and memory in women over time. Alternatively, “good” fats — like the monounsaturated fats in avocados and olive oil — are linked to better brainpower.
Researchers analyzed about 6,000 women over the age of 65 participating in the Women’s Health Study — a cohort of nearly 40,000 women older than 45. The selected women participated in three cognitive-function tests, which were spaced out every two years over a four-year span.
The women filled out detailed questionnaires about their diets and food frequency at the beginning of the study. “Total fat intake was not related to cognitive change, but the types of fats mattered,” says study author Dr. Olivia Okereke of the BWH Department of Psychiatry.
Their findings show women who consumed the highest amounts of saturated fat — found in foods like butter and red meat — performed worse overall on cognitive-function tests over the four-year period. Women who consumed the most monounsaturated fats had better cognition and memory in that same time period.
“Previous literature shows there are important relationships between fats and cardiovascular health,” says Okereke. “Cardiovascular health is also associated with brain aging, so we wanted to look at how this relationship and these fats influence cognitive function.” Okereke speculates the different fats may modify the levels of inflammation in the body; the fats’ influence on overall cardiovascular health may translate into differences in cognitive aging.
“People will want to think about substituting out saturated fat in favor of monounsaturated foods,” says Okereke. “Making that substitution might be a way to prevent cognitive decline in older people.”
Consider some of these foods high in monounsaturated fats as healthier alternatives:
- Olive oil
While you’re at it, avoid overconsumption of these foods high in saturated fats:
- Red meat
- Packaged foods including cookies, crackers and chips
“[C]hoose low or nonfat dairy foods such as fat-free milk and yogurt. Stick with skinless poultry and fish. Limit red and processed meats such as beef, pork, lamb, hot dogs or bologna to a few times a month. Experiment with meatless meals such as veggie burgers, spinach-eggplant lasagna, or black bean, corn and avocado tacos.”
(MORE: Should We All Be Vegetarians?)