Is vitamin D more important than calcium for strong bones?

Howard E. Lewine, MD
It's important to get both vitamin D and calcium. You are hearing more about vitamin D for a good reason. Most people get enough calcium and don't need supplements.

That is not true for vitamin D. We recently discovered that many people have low vitamin D blood levels. Why is this?
  • There are few natural food sources of vitamin D. (Some foods and drinks are fortified with vitamin D. Milk and cereal are examples.)
  • We need the sun to change the inactive form of vitamin D in our skin into the active form. We need the active form for healthy bones and good health. Because of skin cancer and premature aging of skin, we have limited our sun exposure over the years.
I recommend that people take a vitamin D supplement daily. Vitamin D3 is the preferred form (rather than D2). I usually suggest 1,000 International Units (IU) of vitamin D3 per day. This is a slightly higher dose than what is recommended by the Institute of Medicine. But this amount of vitamin D is very safe.
Harvard Medical School Osteoporosis: A guide to prevention and treatment

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.