When it comes to your noggin, not all fats are created equal, with new research finding the same fats that wreak havoc on the body may do the same to the mind. The good news, the fats known to be healthy for the body were also linked to better cognitive function in older women who participated in the new study.
"When looking at changes in cognitive function, what we found is that the total amount of fat intake did not really matter, but the type of fat did," study researcher Dr. Olivia Okereke, of Brigham and Women's Hospital, said in a statement.
The results were published online May 18 in the journal Annals of Neurology.
Bad fats include saturated fats, or those fats found mostly in animal products, and trans fats, which are unsaturated (good) fats that have been partially saturated with hydrogen to extend their shelf life. Trans fats can elevate the unhealthy type of cholesterol (called LDL cholesterol), research has shown. And doctors are pretty much in agreement that eating foods loaded with saturated fats, such as butter, red meat and pork, can cause heart disease, obesity and diabetes.
The new research finds, in particular, saturated fat is associated with worse overall cognitive function and memory in women over time. They also found that a "good" fat — mono-unsaturated fat — was associated with better overall cognitive function and memory. [6 Foods That Are Good For Your Brain]
"Our findings have significant public health implications," Okereke said. "Substituting in the good fat in place of the bad fat is a fairly simple dietary modification that could help prevent decline in memory."
Okereke and colleagues analyzed data from a subset of 6,000 women, all over the age of 65, from the Women's Health Study. The women participated in three cognitive-function tests, which were spaced out every two years for an average testing span of four years. These women filled out very detailed food-frequency surveys prior to the cognitive testing.
Compared with those women who ate the lowest amounts of saturated fats, women in the highest saturated-fat category showed worse overall cognition and memory over the four years of testing. Women who ate the most mono-unsaturated fats, which can be found in olive oil, had better patterns of cognitive scores over time. Trans fats weren't associated with changes in cognition over time, the researchers reported.
These findings could lead to strategies to stave off and prevent cognitive decline in older people. Even subtle declines in cognitive functioning can lead to higher risk of developing more serious problems, like dementia and Alzheimer disease.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.