During both of those surveys, the subjects also rated their overall life satisfaction on a scale of 1 to 10.
Researchers looked at how each person’s fruit and vegetable consumption and happiness changed over those two years, and found that with each extra serving of fruits and vegetables people ate, the happier they felt.
For example, if someone ate two more daily servings of fruit in 2009 than they did in 2007, their happiness increased by about .07 on a 10-point scale.
Based on the strength of that link, the researchers calculated that if someone went from eating no produce to eating eight servings a day, they’d experience a .24 increase in their happiness score.
While that may not sound like much, it’s as large as the boost you’d get from going from unemployed to employed, says study co-author Andrew Oswald, Ph.D., a professor of behavioral science at the University of Warwick in England.
That’s because the researchers also calculated how much happiness was linked to other major factors, like working status. On average, unemployment was associated with a .21 decrease in happiness.
While scientists aren’t certain how fruit and vegetables make you happier, it could have to do with the nutrients they contain.
Past research suggests there is a link between B vitamins—found in spinach, Brussels sprouts, and oranges—and serotonin production, one of the chemicals in your brain that helps produce your happy mood.
One recent study also found a connection between higher concentrations of carotenoids, an antioxidant that gives foods like carrots or tomatoes their rich color, and optimism.
Even if you already eat fruits and vegetables, increasing your intake even more may produce a bump in happiness, says Oswald.
Shoot for eight servings a day—one serving would equal half a cup of fresh, frozen, or canned fruits and vegetables, according to the American Heart Association.
Source: Men’s Health