Sorry, this isn’t a pass to start inhaling burgers, fries, and sticks of butter in the name of happiness. Instead, focusing on the right fats in reasonable quantities could offer the mental-health benefit. “Fat should account for about 25 to 35% of your total daily calories—55 to 78 g on a 2,000-calorie-a-day diet,” says Frances Largeman-Roth, RDN, a nutritionist and author of Eating in Color, who is not affiliated with the study.
Which fats are best? “Omega-3s are highly concentrated in the brain and associated with increased levels of ‘good’ HDL cholesterol,” says Largeman-Roth. “Plus, omega-3 deficiency in adults has actually been linked to mood swings and depression.” Good sources include fatty fish like albacore tuna, salmon, herring, sardines, and cod; grass-fed meats and dairy; pasture-raised eggs; and chia, flax, and hemp seeds. (Tryflaxseed oil in a smoothie.)
Foods rich in monounsaturated fats such as avocados, almonds, and olive oil hold promise, too—they’ve been linked to increased levels of HDL as well as improved cognitive function. Saturated fats and trans fats, on the other hand, have been associated with an increased risk of depression.
But eating more high-quality fats isn’t the key to happiness for everyone, experts say. Very low cholesterol—as well as depression—could also be due to any number of factors, such as an underlying illness, another nutrient deficiency, certain medications, or a genetic resistance to dietary cholesterol. So your individual case of the blues may not necessarily be cured with diet changes alone.
Bottom line: If you’re feeling depressed, definitely don’t shun healthy sources of fat—but also be sure to work with your doctor to see if there may be underlying issues at play.