Calcium & Vitamin D

How important are calcium and vitamin D for bone health?

Calcium and vitamin D are essential components for building and maintaining strong bones throughout life.  While there has been some controversy in the past few years on how much calcium and vitamin D should be recommended for healthy bones, there are no doubts that too many people in the U.S. and in many other countries, especially elderly, frail people, do not take enough of these nutrients, and this can cause loss of bone and decreased bone strength.

The body needs calcium for building and maintaining bones and teeth but also for other essential functions, including, for example, nerve conduction, muscle contraction, and blood clotting.  Each day, we lose calcium through urine, feces, sweat and skin, and the only way to make up for these obligated losses is through dietary intake.  Likewise, although the body can manufacture vitamin D in the skin by sunlight irradiation, for many people this is not a suitable or sufficient source of the vitamin.  Hence, the diet must provide the required amount of vitamin D.

How much calcium and vitamin D should I take?

The Bone Health Program follows the recommendations for calcium and vitamin D intake set forth by the National Osteoporosis Foundation, and also endorsed by other professional organizations, with some variations:

Calcium Requirements for Women
Age 50 & younger 1,000 mg daily
Age 51 & older 1,200 mg daily


Calcium Requirements for Men
Age 70 & younger 1,000 mg daily
Age 71 & older 1,200 mg daily


Vitamin D Requirements for Women and Men
Under age 50 400-1,000 international units (IU) daily
Age 50 and older 1,000-1,200 IU daily


It is important to consider that the daily needs of calcium and vitamin D vary with age and gender; requirements are higher in growing children and pregnant women, as well as in the elderly, whose efficiency in absorbing calcium through the intestine declines.  Ideally, your diet (and sunlight) would provide all the calcium and vitamin D you need all year around; in reality, very few people follow diets that meet the calcium and vitamin D requirements.  This is where “supplements” become handy.   Calcium and vitamin D supplements should be used as they are meant to be used, to supplement the diet that does not provide enough of these nutrients.  Thus, the amount of supplements must be tailored to everyone’s individual needs.

You can download these Bone Health Program tables to help you determine how much calcium and vitamin D comes from your typical diet, and thus, how much supplement you should consider taking.

Are calcium and vitamin D supplements safe?

In recent years, there has been some controversy about the safety of calcium supplements.  Some researchers found a slight but significant increase in heart attacks in patients who were taking calcium (not vitamin D) supplements[i].  However, other studies have not confirmed such findings[ii]; others even concluded that calcium and vitamin D supplementation if anything, reduces the risk of atherosclerosis[iii].  Our recommendations are consistent with guidelines published by major professional organizations and reflect decades of clinical practice.  The bottom line is that if you follow the recommendations noted above and take the amount of calcium and vitamin D supplements that is right for you, you will meet your daily needs of these vital nutrients without any risks.

If you want to know more about calcium and vitamin D, you can visit The National Osteoporosis Foundation website, which contains additional useful tips and tools on these topics.

We recommend that you always contact your health care provider before making decisions on over the counter medications or supplements, or if you have diseases or conditions that may affect your calcium and vitamin D intake, or that may contraindicate your taking such supplements.


[i] Bolland et al. British Medical Journal 342:d2040; 2011

[ii] Alcantara Cunha Lima et al. Archives of Endocrinology and Metabolism 60:252-263;2016

[iii] Thiele et al. Atherosclerosis 241:743-751; 2015



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