Ask the expert: How do fats affect my mental health?
Today’s media bombards viewers with the idea that good fats and bad fats have clear and separate impacts on physical and even mental wellness.
Western diets (including those of eaters in the U.S.) contain foods that are often loaded with refined sugars and, more importantly, saturated, or “bad” fats. These saturated fats are sourced from animal products and have been shown to reduce performance on tasks of memory, such as word recall or object recognition tested after a short delay, in both human and animal subjects. Controlled studies in rodents even suggest that these memory impairments can be seen after exposure to high fat diets for as short as one week’s time. Recent research in human participants also links extended, lifelong consumption of saturated fats to an increased risk of mild cognitive impairment and dementia.
Polyunsaturated and monounsaturated fats, the “good fats” found in seafood, nuts, and olive oils and a staple of the Mediterranean diet, have more recently been linked to reduced incidence of dementias and improved memory performance later in life in human participants.
These positive effects on mental wellness may begin prior to birth, as pregnant mice maintained on diets higher in polyunsaturated fats produce offspring with better object recognition memory than those born to mothers maintained on a diet deficient in these fats.
Overall, these findings support a positive role for unsaturated fats in healthy mental aging, but most of these diets still include saturated fats, suggesting these findings are not as simple as reducing all saturated fat intake.
Does a shot of olive oil a night keep the memory doctor away? Not likely, as lifetime exposures to a healthy (yet still unknown) ratio of saturated to unsaturated fats appears key, with current research aiming to determine the specific components of this yet unknown ideal diet. Perhaps substituting wild-caught salmon for your favorite cut of steak can, together, reduce vulnerability to age-related memory decline given the growing rates of dementia-related disorders in the aging population.
Making good food choices early in life appears the best answer to what one can do to better protect one’s memory from a lifetime of saturated, fat-induced forgetfulness.