The unhealthy fats found in margarine, donuts, and fast food take a toll on more than your waistline— they can also increase your risk of depression, according to a Spanish study of more than 12,000 people published in the journal PLoSONE.
Researchers at the University of Las Palmas de Gran Canaria in Las Palmas, Spain found that subjects who ate the most trans fats had up to a 48 percent increased risk of depression. The more trans fats a person ate, the worse he or she felt.
In contrast, subjects who ate diets rich in olive oil had a 30 percent lower risk of depression than those who never ate olive oil or just used a little of it. And the more olive oil they consumed, the happier they were.
It’s possible that trans fats trigger depression because they increase inflammation in the body, say the authors. Inflammation is a risk factor for both depression and cardiovascular disease.
Olive oil contains compounds with anti- inflammatory properties, which may help the circulatory system function better.
What does it all mean? In short, populations eating higher levels of trans fats—say, Americans—are at an even greater risk of depression. Previous research has also linked trans fats, which are created through a process that adds hydrogen to oil, to increased heart risk.