Do I need a vitamin D supplement?
The short answer
Only if you are low, or at risk of being low. A very large trial found that giving vitamin D to generally healthy adults who were not deficient did not reduce fractures. For people who are deficient, or who have osteoporosis, correcting vitamin D is important. A blood test tells you which group you are in.
Choose your depth
Only if you are low, or at risk of being low. A very large trial found that giving vitamin D to generally healthy adults who were not deficient did not reduce fractures. For people who are deficient, or who have osteoporosis, correcting vitamin D is important. A blood test tells you which group you are in.
Choose Detailed for the fuller picture, or Scientific for mechanisms and study data.
Vitamin D helps the body absorb calcium from food. Despite abundant sunshine, low vitamin D is common in India because of indoor lifestyles, covered skin, pollution and darker skin, which needs more sun to make the same amount.
What the largest trial found
The VITAL trial gave 2000 IU of vitamin D3 a day, or a placebo, to almost 26,000 generally healthy adults for about five years. Vitamin D did not reduce fractures. Crucially, most participants were not deficient to begin with.
So who benefits?
People with confirmed deficiency, osteoporosis, limited sun exposure, certain digestive or kidney conditions, or who take medicines that affect vitamin D. For them, correcting the level matters.
A sensible approach
Ask your doctor whether a 25-hydroxy vitamin D blood test is right for you. Combine any treatment with calcium-rich food, safe sun exposure and weight-bearing activity.
LeBoff et al. (2022), an ancillary study of VITAL (n = 25,871, median follow-up 5.3 years), found no effect of cholecalciferol 2000 IU daily on total fractures (HR 0.98), non-vertebral fractures (0.97) or hip fractures (1.01). The population had a mean baseline 25(OH)D above deficiency thresholds and was not selected for low bone mass.
Calcitriol, the hormonal form, is used therapeutically in specific conditions such as renal bone disease and hypoparathyroidism; its use requires monitoring of serum calcium.
What we know
- Vitamin D is essential for calcium absorption.
- Supplementing people who are not deficient does not reduce fractures.
- Deficiency is common and correctable.
What remains uncertain
- The ideal blood level for different people.
- Whether vitamin D affects conditions beyond bone.
The evidence
Related ingredients
Sources
- LeBoff MS, Chou SH, Ratliff KA, et al. Supplemental vitamin D and incident fractures in midlife and older adults. N Engl J Med. 2022;387(4):299-309.
- Knapen MHJ, Drummen NE, Smit E, Vermeer C, Theuwissen E. Three-year low-dose menaquinone-7 supplementation helps decrease bone loss in healthy postmenopausal women. Osteoporos Int. 2013;24(9):2499-2507.
Last updated 15 October 2026.
This is educational content and does not replace advice from a qualified doctor. If you have symptoms or take medicines, please speak to your doctor before making changes.
