CancerVitamin D

Vitamin D: How much is enough?

Current recommended daily intakes of vitamin D are 200 international units (IU) for younger adults, 400 IU for those aged 51 to 70 years, and 600 IU for those older than 70 years.

A review published in the American Journal of Clinical Nutrition contends that the optimal 25-hydroxyvitamin D (25(OH)D) level based on clinical evidence is between 90 and 100 nmol/L and the associated vitamin D intake recommended to maintain these levels for 50% of adults is 700 to 1000 IU/day.

This conclusion was based on an analysis of studies of bone mineral density, fracture prevention, lower extremity function, falls, oral health, and colorectal cancer.

To achieve the levels suggested in the review article, cod liver oil is likely to make a comeback. The National Institutes of Health lists sources of vitamin D here.

7/26/06 21:13 JR

Hi, I’m JR

John Russo, Jr., PharmD, is president of The MedCom Resource, Inc. Previously, he was senior vice president of medical communications at, a complementary and alternative medicine website.