Vitamin D3, also known as cholecalciferol, is a fat-soluble vitamin that is involved in skeletal health, the immune system, cell growth, muscle function and more. It is one of the few nutrients that your body can produce on its own through skin cells, in response to sun exposure. Vitamin D3 can also be taken through the diet and as a dietary supplement. Unfortunately, vitamin D deficiency is common, and some groups are at a higher risk of deficiency. Especially older adults, those whit limited sun exposure, people who are overweight or people with dark skin - are at greater risk of having a deficiency of this important vitamin.

Vitamin D3 & Vitamin D2 - what's the difference?

Vitamin D comes in two forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D3 is found mainly in animal foods, such as fish, liver, eggs and fish liver oil. Vitamin D3 in dietary supplements can come from both animals (usually from sheep wool) or from vegetables, such as. lichen or algae. Vitamin D2 is mostly found in mushrooms, as well as foods fortified with vitamin D2, as well as in dietary supplements.

The biggest difference between vitamin D2 and vitamin D3 actually lies in the way they are metabolized in the body. A study published in the "Journal of endocrinology and metabolism" found that vitamin D3 increased vitamin D levels in the blood twice as effectively as vitamin D2 (1).

For this reason, a dietary supplement with vitamin D3 is recommended, as it optimizes the absorption in the body and provides the most value for money. A dietary supplement with vitamin D3 is also an effective way to increase calcium absorption in the body and promote skeletal health, to name a few benefits.