Your mom always admonished you to make sure you cleaned your plate at every meal and finished all of your fruits and veggies—not because she was a nag who has to control everything you do, of course, but because she wanted you to grow up to be big and strong and healthy.

Now that you’re an adult, hopefully you’ve continued to follow her advice and down lots of fruits and vegetables every day. Here’s why: Eating lots of produce not only helps you lose weight, strengthen your heart, and make you all-around healthier, but also help improve your personality and outlook on life, according to new research from the University of Otago in New Zealand. Think of fruits and veggies like a therapist made out of food. (Thanks, mom).

In the experiment, scientists divided up 171 students, ages 18–25, into three groups for two weeks. One group ate normally, while the other got daily personal deliveries of two extra servings of fresh fruits and veg, The third received vouchers for free produce, and texts telling them to eat more fruits and vegetables, kind of like a digital pest (erm, personal nutritionist).

At the end of the two weeks, those who were personally handed the produce showed improvements in psychological well-being, like “vitality,” “motivation,” and “flourishing,” with the other two groups showing no such developments. The researchers also didn’t find any change to symptoms of depression or anxiety in any group tested.

The study authors noted that to get people to consume more fruits and veggies, it may not be as simple as putting up some posters or digitally prompting people to get their daily dose in: “Perhaps greater emphasis needs to be placed on actually providing people with fresh FV—stocking more FV in dorms, cafeterias, workplaces, substituting fruit for dessert, and offering free fruit for people when they shop,” the authors wrote. (SO THERE: Nagging never works, and science just proved it.)