Vitamin D Requirements

Today, more people are spending time inside and when they do go outside, they often cover up to protect against the sun’s harmful rays. Moreover, wearing sunscreen with a sun protection factor (SPF) of 8 or more inhibits vitamin D production in the skin by more than 95%.

The last updates made to the vitamin D recommendations occurred in 1997 and were made primarily for the prevention of bone disease, such as rickets in children and osteoporosis in the elderly. The current guidelines recommend 200 to 600 international units (IU) a day; some believe this number should be increased to 2,000 IU, perhaps following the Canadian Cancer Society’s recent increase to 1,000 IU.
Importantly, recent studies indicate vitamin D is beneficial for much more than bone diseases.

In addition, evidence suggests vitamin D deficiency plays a role in many diseases, such as high blood pressure, heart disease, tuberculosis, the flu, multiple sclerosis, rheumatoid arthritis, schizophrenia, depression and many forms of cancer—including colon, breast, ovarian, prostate and, ironically, skin cancer. While prolonged sun exposure is not recommended because of increased cancer risk, it seems a little sunlight may do more good than harm. Unfortunately, some in the medical community don’t believe sufficient evidence exists to warrant a change in the federal guidelines.