Vitamin D3 is essential for strong bones, immunity, and overall health; learn about its benefits, dosage, deficiency symptoms, food sources, and safe usage. Vitamin D is a category of vitamins that includes vitamins D2 and D3. D2 is found in some plants. Your body creates D3 from sunlight. Vitamin D3 is important for brain health, strong bones, and anti-cancer properties. Learn which 5 foods to eat to get more Vitamin D3. Vitamin D3 helps your bones by improving calcium and phosphorus absorption. Low vitamin D3 levels can affect your mood and lead to feelings of sadness or anxiety. Vitamin D3 boosts your immune system by helping fight infections and controlling inflammation. Cholecalciferol is vitamin D3. Vitamin D helps your body absorb calcium. Vitamin D is also essential for maintaining a healthy immune system. The function of the immune system is to prevent or limit infection. Cholecalciferol is used as a dietary supplement in people who do not get enough vitamin D in their diets to maintain adequate health. Vitamin D (calciferol) keeps bones strong and supports your immune system. People ages 1 to 70 need 15 mcg (600 IU) per day; people 70+ need 20 mcg (800 IU). Taking a vitamin D supplement or a multivitamin with vitamin D may help improve bone health. The recommended daily amount of vitamin D is 400 international units (IU) for children up to age 12 months, 600 IU for people ages 1 to 70 years, and 800 IU for people over 70 years. Which vitamin D is right for you? The dose is only half of it. If your vitamin D doesn’t fit how you take it, you may not be getting what you think. Several forms (vitamers) of vitamin D exist, with the two major forms being vitamin D 2 (ergocalciferol), and vitamin D 3 (cholecalciferol). [1] The common-use term vitamin D refers to both D 2 and D 3, which were chemically characterized, respectively, in 1931 and 1935. Vitamin D3 helps your body absorb calcium, which is essential for healthy bones. Direct sunlight, foods like fatty fish and fortified dairy, and supplements are good sources of Vitamin D3.