Vitamin D is a fat-soluble vitamin that you can get from sunlight, some foods or supplements. When your skin is exposed to the UV rays, it starts changing cholesterol present in the body to Vitamin D.
According to a study by the University of Alberta Faculty of Medicine & Dentistry that was published in the journal Scientific Reports, sunlight shrinks fat cells and can aid in weight loss. When our skin penetrates the blue-light wavelength and it reaches the fat present under the skin, lipid droplets shrink and are released out of the cell. In simple words, sunlight helps to get rid of all the extra fat of the body. Deficiency of this nutrient is also linked with obesity. This can also be established by the fact that people gain more weight in winters due to weaker UV rays.