A diet high in monounsaturated fatty acids may be associated with less cognitive decline in older healthy women, according to a study published in the Journal of the American Geriatrics Society. Previous research has linked cognitive decline with cardiovascular disease, and certain types of dietary fatty acids (saturated and trans) are a known risk factor for cardiovascular disease. However, in this study, no association was found between cognitive decline and saturated or trans fatty acids. Monounsaturated fats are found in olive and canola oils, and saturated fats are found in coconut and palm oils as well as in butter, cheese, milk, and fatty meats. Trans fats are found in some margarines, commercial baked goods, and other foods made with or fried in partially hydrogenated oil.
Researchers analyzed the dietary intake of 482 women aged 60 and older from a food frequency questionnaire, and assessed their cognitive function—memory, vision, executive function, language, and attention—upon enrollment and again after 3 years. The study is part of a larger observational study that examined associations between dietary and lifestyle factors and cognitive function in older women without dementia.
The researchers found that a higher intake of dietary monounsaturated fatty acids was associated with less cognitive decline over a 3-year period. Further, after testing for associations between monounsaturated fatty acids and individual components of cognitive function, the researchers found that greater intake of monounsaturated fatty acids was associated with less decline in visual-spatial ability and memory after adjusting for other factors (i.e., age, education, reading ability). In addition, higher intakes of saturated fatty acids, trans-fatty acids, and dietary cholesterol were not associated with cognitive decline after adjusting for other factors.
The researchers noted that monounsaturated fatty acids have anti-inflammatory effects and suggested that these effects may provide one explanation for their protection against cognitive decline (as chronic inflammation appears to be one contributor to Alzheimer’s disease). Limitations of this observational analysis include the small sample size and the use of a study population consisting primarily of healthy, educated Caucasian women, which the researchers noted may limit the generalizability of findings to other populations.
See also: Fish oil's positive impact on cognition and brain structure