Science has long touted the health benefits of “good”—or monounsaturated—fats and the harms of “bad”—or saturated—fats. The data continues to pile up—and new research indicates that bad fats may actually impair overall brain function and memory over time. In contrast, good fats seem to improve brain function and memory. These results were published in the Annals of Neurology and suggest that fats may have the same effect on the brain that they do on the heart.
The study included data from 6,183 women who took part in the U.S. Women’s Health Study. The women filled out detailed food questionnaires at the beginning of the study and then again prior to several brain tests over the course of the study. They took three brain function tests every two years over a period of four years.
The results indicated that over time, women who ate the highest amounts of saturated fat (such as red meat and butter) had the worst overall brain function and memory compared to women who ate the lowest amount of saturated fat.
In stark contrast, the women who ate the most monounsaturated fats (such as olive oil and other vegetable oils) scored higher on brain tests over the course of the study, compared to their counterparts who consumed fewer monounsaturated fats.
The results of this study add to the evidence that is stacking up against saturated fat. It has been associated with increased abdominal fat storage and an increased risk of heart disease, cancer, diabetes, and Alzheimer’s disease.
In other words, cognitive function is an addition to the long list of reasons to reduce your intake of saturated fat. To stay healthy for the long-term, it’s best to limit intake of saturated fats and increase intake of monounsaturated fats such as fish oil, olive oil, nuts, and seeds.
Millions of older people suffer from declining cognitive function. This latest research could help identify ways to prevent this decline.
Okereke OI, Rosner BA, Kim DH, et al. Dietary fat types and 4-year cognitive change in community-dwelling older women. Annals of Neurology. Published early online May 17, 2012. DOI: 10.1002/ana.23593