If you’re in need of a little more glee, here are six research-backed “better mood foods” to build into your eating repertoire.

Probiotic-rich foods

In a recent Dutch study, 20 healthy volunteers received either a probiotic supplement or a placebo for four weeks. Those who received the real deal showed a significantly reduced reactivity to sad mood, which was largely due to a reduction in aggressive thoughts and rumination (you know, when you over-think or obsess on the negative). The conclusion: the type and amount of bacteria in your digestive tract impacts your mood. Scientists even have a name for it: the gut-brain axis, or the communication highway between the GI tract and the brain, and it’s fascinating.

In an animal a study conducted at McMaster University in Ontario, gut bacteria from mice with different personalities were swapped. Fearless mice became timid after receiving gut bacteria from anxious counterparts, and the reverse was also true -- fearful rodents became more expressive and less apprehensive. The researchers also found that aggressive mice became calm when scientists changed their gut microbes by health-ing up their diets. All of this means that, for all intents and purposes, your gut bacteria can literally be mind-altering.

Fruits and veggies

In a study published in the British Journal of Health Psychology, nearly 300 young adults kept daily food journals for three consecutive weeks, in addition to completing psychological and mood-related ratings. Researchers found that a higher intake of produce resulted in more energy, calm and a greater sense of happiness. They also noted that the effects were seen not only on the days more veggies and fruits were consumed, but also throughout the following day. Another study, published in the journal Social Indicators Research, which tracked 80,000 adults, found that consuming a higher amount of produce boosted mental well-being, with the magic number for happiness being seven daily servings. To use produce to elevate your mood, choose fruits and veggies first and build each meal around them.

Coffee

Coffee drinkers can be thought of as curmudgeons, but research has actually linked regular java consumption to positivity. In one study, researchers found that coffee consumed in the morning was linked to energy, kindness and pleasure. Coffee enjoyed socially was tied to affection, friendship, satisfaction, and good nature; and when sipped leisurely, cups of Joe induced calm, happiness and tranquility. Another study, published in the JAMA Internal Medicine, found that women who drank two to three cups of coffee a day were 15 percent less likely to develop depression over a 10-year span, compared to those who consumed one cup or less each day. Now that doesn’t mean a pot a day is a recipe for bliss, but if you enjoy coffee there are other health benefits to making it a daily habit. Check out my previous posts 6 Reasons to Keep Loving Coffee and 5 Reasons to Drink Coffee Before a Workout.

Dark chocolate

Even thinking about dark chocolate brings a smile to my face, but research backs its happiness benefits. The antioxidants in dark chocolate can trigger the walls of your blood vessels to relax, lowering blood pressure and improving circulation. That may be why one study found that eating about an ounce and a half of dark chocolate daily for two weeks reduced levels of stress hormones in people who rated themselves as highly stressed. Dark chocolate also contains magnesium, a mineral that has been shown to help alleviate PMS symptoms, including fatigue, depression and irritability. Finally, dark chocolate’s unique natural substances trigger a sense of euphoria that’s similar in to the feeling of being in love!

Mushrooms

I adore mushrooms. In a previous post I wrote about five surprising benefits of this underrated superfood, and due to their unique nutrients, mood regulation may be a sixth. Shrooms are rich in selenium and research has linked a deficiency of this mineral (which doubles as an antioxidant) to a higher risk of depression, anxiety and fatigue. Mushrooms are also the only plant source of natural vitamin D, a key nutrient of us aren’t getting enough of. In a study of people with seasonal affective disorder, which affects 11 million Americans, scientists found that those who upped their vitamin D intake experienced an enhanced mood. To bolster your intake, incorporate mushrooms into omelets or quiche at breakfast, salads at lunch and sauté, grill, or oven roast them at dinner.

Green tea

A Japanese study, conducted with more than 40,000 people, found that levels of psychological stress were 20 percent lower in people who drank five or more cups of green tea per day compared to those who drank less than one. The results held true even after other factors were accounted for, including age, sex, medical history, body mass index, alcohol consumption, cigarette smoking and diet. Reach for green tea as a beverage, or incorporate loose tea leaves or brewed green tea into cooking. It’s fantastic in smoothies, marinades, soups and sauces.