One advantage of moderate sunlight exposure is that it increases the production of serotonin, the “feel-good" hormone. 

But besides being produced by sunlight exposure, serotonin is elevated significantly by eating excessive amounts of refined carbohydrates, such as ice cream and snack cakes. However, diets high in refined carbohydrates have been linked with a significantly increased risk of obesity, so it's healthier to get your serotonin by sunlight rather than junk food!