We all know what we're supposed to do about food. Eat more fruits and vegetables, less red meat, fewer sweets, drink less beer, yadda yadda. The advice, of course, sounds specifically designed to make life less pleasurable, if longer. And yet: Two recent studies suggest that going ultra virtuous in the diet department actually made people feel happier.
A study published this month in the American Journal of Public Health looked at the impact of fruit and vegetable consumption on happiness and found that with more produce, apparently, comes more joy. Researchers tracked more than 12,000 people over the course of several years, via food diaries and regular psychological check-ins. Lo and behold, people got incrementally happier with every serving of fruit and veg they ate, up to eight a day. This study didn't look at why the Prozac-like effect, but the lead author was willing to hazard a guess: "In the long run," study author Andrew Oswald, a behavioral economist at the University of Warwick in the UK, told VICE, "I reckon we will discover that it is all because of folate, carotene, and the micro-organisms that make up our gastrointestinal tract."
Indeed, at least one study has suggested that there's a connection between higher blood levels of carotenoids, a type of antioxidant that's plentiful in fruit and vegetables, and an increase in optimism. And recent research has established some interesting links between mental health and the bacteria residing in our guts, which secrete chemicals like serotonin and dopamine—the very same neurotransmitters that regulate mood in our brains. One small study out of Norway, for instance, found a link between certain bacteria in feces (which, of course, is directly linked to the foods we eat) and levels of depression.
The more advanced version of achieving happiness through food involves simply eating less of it: A recent study in JAMA Internal Medicine reports that when 100-odd men and women ate 25 percent fewer calories than normal for two years (with regular nutrition consultations to keep them on track), they reported getting better sleep after the first year compared to the people in a control group. After two years of dieting, the dieting group had improved moods, better sex drives, and better overall health. Which could be related to the fact that they also lost 17 pounds, while the non-dieters didn't lose much of anything.
Of course, there's not much that's worse than sustained caloric deprivation, so your commitment to happiness would have to be pretty high to eat 25 percent less food all the time. Oswald, of the fruit and vegetable study, has the right idea: "In the short run," he said, "my advice is simpler. Just eat up as many fruit and veg as you can and lie back and enjoy your life."