As mentioned above, vitamin D supplements are not usually required unless you are at risk of vitamin D deficiency. Vitamin D is sometimes included in multivitamin supplements. If you choose to take vitamin D supplements, 10 micrograms a day will be enough for most people.
Do not take more than 100 micrograms (4,000 IU) of vitamin D a day as it could be harmful. This applies to adults, including pregnant and breastfeeding women and the elderly, and children aged 11–17 years. See how much vitamin D you need and if you can get too much of this vitamin here.
Some people are at risk of more severe vitamin D deficiency, and need higher doses of vitamin D supplements (colecalciferol) because of having specific health conditions. Examples include:
In chronic kidney disease, damage to your kidneys affects the metabolism of vitamin D. People with severe kidney disease may require vitamin D supplements such as alfacalcidol (One alpha®) or calcitriol (Calcitriol-AFT®), and other supplements such as calcium.