The outdoors can have numerous benefits on your body. First and foremost, the sun stimulates the production of Vitamin D in your body. As Healthline explains, vitamin D helps regulate the absorption of calcium and phosphorous, while also facilitating normal immune system function. Exercising outside has been proven to help prevent heart disease, stroke and obesity. That being said, whether it be sitting outside reading a book or running a nature trail, being outside will help boost serotonin levels and fight depression — ultimately leading to a healthy and happy mind and body.