Many people are looking for scientifically-based guidelines on fat intake and cognitive decline. There is a lot of confusion about which dietary fats can benefit brain health and which can cause harm. And just how much fat is too much? What’s the optimal amount of fat, and what are the most beneficial and harmful types, if the goal is to maintain cognitive function in aging?
A new study compared dietary fat intake by type and amount to offer recommendations. The research was conducted in a cohort of over 6,000 healthy older women. Over a five year period, the people who consumed more saturated fat did worse on cognitive and memory tests, while those who consumed more monounsaturated fat did better. Data from polyunsaturated fat and trans fats did not show positive or negative correlations with cognitive factors. Interestingly, the researchers concluded that total fat intake does not seem to influence how the brain ages; what matters is what types of fats are consumed.
To sum up these findings: eating saturated fat may harm the brain; eating monounsaturated fat may boost it. Polyunsaturated and trans fats don’t appear to have an effect either way. The amount of fat you eat doesn’t appear to make a difference; what matters is the type.
Saturated fat is found in animal products, like beef, lamb, pork, chicken skin, butter, cream, and cheese. Monounsaturated fat is found in olive oil, canola oil, sesame oil, other nut oils, nuts, avocados, and seeds.
Polyunsaturated fat is found in cold-water fish like salmon and mackerel, as well as in corn oil, soybean oil, and sunflower oil.
The USDA recommends getting 20-35% of daily calories from fat. For a 2,000 Calorie diet, that amounts to 44 to 77 grams of fat per day.
You can read the abstract in the Annals of Neurology.