Last month, we found out that even just a few minutes of exercise can improve your mood. And now, we're learning that certain kinds of foods have an effect on your happiness level, too. According to a study published in PLOS One, fruits and vegetables aren't just great for your physical health — they can work wonders on your mental health, too. For the study, researchers examined a group of young adults who didn't usually eat fruits and veggies (the participants were mostly comprised of young women aged 18-25), and split them into three groups. One group received two additional servings of fruits and vegetables per day, one received texts reminding them to eat fruits and veggies as well as vouchers to buy them, and another group continued their eating habits as usual. At the beginning and end of the study, the participants were given psychological assessments that evaluated factors of their mental health, such as their mood, vitality, motivations, and symptoms of depression and anxiety. After just 14 days, researchers found that the group who received fruits and vegetables incorporated them more into their meals, and experienced improved psychological well-being. Though researchers noted that the study didn't find improvements in symptoms of depression and anxiety, they believe that since the participants' moods improved in such a short span of time, a longer study could be useful for those results. The study further reiterates that even small changes can make big differences. If you're feeling inspired to add a little more produce to your meals, check out a guide on picking the best fruits and vegetables.