You're 112% More Likely To Get Depressed If You're Not Eating THIS

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Until recently, we've been told to shun fat and cholesterol to save our hearts—eating too much, experts said, would put us at greater risk for heart attack, stroke, and early death. But instead of improving our health, could the "fat is bad" dogma of the '90s and early 2000s be partially to blame for the uptick in depression and suicide?

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That might be a bit of a leap, but a compelling new meta-analysis in the Journal of Psychiatry & NeuroscienceJournal of Psychiatry & Neuroscience makes you wonder. It found that low levels of blood cholesterol—potentially caused by inadequate fat in the diet—were associated with a greater risk of being deeply depressed or suicidal. In fact, people with the lowest cholesterol levels had a whopping 112% higher risk of suicidal thoughts.

But why? One theory: Because the brain is 60% fat and about 25% your body's cholesterol is found there, the brain can't function optimally without sufficient levels of those nutrients. In fact, some individual studies show that very low cholesterol impairs your ability to effectively synthesize and transport neurotransmitters like mood-boosting serotonin.

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. (Try flaxseed 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.