Vitamin D—nicknamed the "sunshine vitamin" due to its ability to be absorbed by the body through sunlight—is a major player in keeping the human body healthy. Its main job, according to the National Institutes of Health's Office of Dietary Supplements, is to promote calcium absorption, making it necessary for bone growth and bone remodeling (when mature bone tissue is removed and new bone tissue is formed). Because of that, a lack of vitamin D can lead to thin, brittle, or misshapen bones. But vitamin D offers a range of other benefits too, ranging from positives for both physical and mental health. Here are nine vitamin D benefits you need to know about—including ways to get more of the vitamin in your daily diet.