Vitamin D2
Also called: ergocalciferol, vitamin D2 supplement
What it means
Vitamin D2 (ergocalciferol) is a plant-based form of vitamin D used in supplements and prescriptions to help the body absorb calcium.
Vitamin D2 can help maintain the vitamin D levels your body needs to absorb calcium, which matters for keeping bones strong as you age.
Vitamin D2, also called ergocalciferol, is one of the two main forms of vitamin D used in supplements and fortified foods. The other form, vitamin D3 (cholecalciferol), is the kind your skin makes from sunlight. Both D2 and D3 need to be processed by your liver and kidneys before your body can use them, turning into the active hormone that helps you absorb calcium.
D2 usually comes from plant or fungal sources, like irradiated yeast or mushrooms, which makes it a common choice in vegetarian supplements and in prescription-strength vitamin D doses. Research has found that D3 tends to be more effective than D2 at raising and maintaining blood vitamin D levels over time, which is one reason many doctors prefer D3 for everyday supplementation.
Whether D2 or D3 is right for you depends on your individual health, diet, and blood test results, so it's worth discussing with your doctor rather than guessing. Getting enough vitamin D, in whichever form, supports calcium absorption and bone health, but no supplement by itself treats or reverses conditions like osteoporosis.
How sure is this?
Graded Established Science: Supported by broad scientific consensus and decades of research. Read each study with its grade in mind. One study is a piece of the picture, not the whole of it.
Vitamin D2 is a plant-based supplement form that helps your body absorb calcium for stronger bones.
Where this leads
WordYou just read about D2 as one form of vitamin D. Curious what vitamin D actually does for your bones overall?
Where the Academy teaches it
This page is the short version. The lessons teach it in full, with the context around it and a quiz to lock it in.
Related words
Vitamin D is a nutrient that helps your gut absorb calcium so it can be used to build and maintain bone.
Vitamin D deficiency means your body doesn't have enough vitamin D, which is needed to absorb calcium and keep bones…
Vitamin D toxicity is when too much vitamin D builds up in the body, usually from very high supplement doses,…
A 25-hydroxy vitamin D test is a blood test that checks how much vitamin D you have in your body, which is important…
Calcium is the main building-block mineral in bone, and since your body can't make it, you need to get it from food…
A vitamin D loading dose is a short-term, high-dose course of vitamin D used to correct a deficiency faster than…
Education only, not medical advice. Decisions about tests, medications and treatment belong with your own doctor. OsteoStrong does not diagnose, treat or cure any disease.
