It is commonly known as the sunshine vitamin, although it is actually a hormone. It is important to have a blood test for Vitamin D levels in order to determine the appropriate dosage, as it is a water-soluble vitamin that needs to be monitored to ensure the dose is sufficient but not excessive. Among its benefits, it helps prevent 17 different types of cancer, insulin resistance, and cardiovascular or respiratory diseases. All cells in the body have receptors for this hormone, making it a vital supplement for overall health.