Recent Blog Articles
If cannabis becomes a problem: How to manage withdrawal
Corneal transplants becoming more common
An emerging treatment option for men on active surveillance
Gun violence: A long-lasting toll on children and teens
Adult female acne: Why it happens and the emotional toll
Talking to your doctor about your LGBTQ+ sex life
Untangling grief: Living beyond a great loss
Thunderstorm asthma: Bad weather, allergies, and asthma attacks
Heart problems and the heat: What to know and do
I’m too young to have Alzheimer’s disease or dementia, right?
How much vitamin D should I take?
Ask the doctor
Image: © Boarding1Now/Thinkstock
Q. I'm confused about vitamin D. How much should I take?
A. There's considerable controversy as to whether most people should take a vitamin D supplement at all. Most of the vitamin D in our bodies is made by our skin, when it is exposed to sunlight. In contrast to most other vitamins, we don't get much vitamin D in our diet. Authorities recommend, however, that children from age 1, and adults through age 70, take 600 international units (IU) daily, and that adults 71 years and older take 800 IU daily. People with, or at risk for, certain bone diseases need to take more than this amount. There's general agreement that doses above 4,000 IU daily can be toxic to adults, with lower doses toxic to kids.
To continue reading this article, you must log in.
Subscribe to Harvard Health Online for immediate access to health news and information from Harvard Medical School.
- Research health conditions
- Check your symptoms
- Prepare for a doctor's visit or test
- Find the best treatments and procedures for you
- Explore options for better nutrition and exercise
I'd like to receive access to Harvard Health Online for only $4.99 a month.Sign Me Up
Already a member? Login ».
As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles.
No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.
Free Healthbeat Signup
Get the latest in health news delivered to your inbox!