The short answer from a rheumatologist and an Ob/Gyn
Q: What is the difference between vitamin D2 and D3, and which one should I take for bone health?
A: There are two types of vitamin D: There’s D2, and that’s usually the prescription that doctors write. It’s plant-based and comes in a 50,000 unit D2 capsule. Vitamin D3 is over-the-counter, so you can just pick it up off the shelf. That’s an animal-derived product.
D3 may be a little more potent than D2, but there’s not a huge difference, so either is fine. Consistency is the key.
We should probably mention the optimal vitamin D blood level, because that’s also an area of confusion. The National Institute of Medicine guidelines say anything over 20 ng/mL is adequate for the general population. But for people who are having a lot of achiness, or those with osteoporosis, many of us would feel that that’s sub-optimal. We would try to strive for over 30 ng/mL – ideally 40 to 50 ng/mL.