Vitamin D has long provided significant support for healthy bone density. However, scientists have validated the critical role that vitamin D plays in regulating healthy cell division and differentiation, and has profound effects on human immunity. These findings link a deficiency of vitamin D to a host of common age-related problems. As a result of this research and startling evidence of a widespread vitamin D deficiency, prominent nutritional scientists are calling on Americans to increase their vitamin D intake to 1000 IU per day and higher. The current RDA is only 400 IU.

Vitamin D is synthesized in the body from sunlight. But, due to the winter season, weather conditions, and sunscreen blockers, the body’s ability to produce optimal vitamin D levels may be inhibited. In fact, it has been proposed that annual fluctuations in vitamin D levels explain the seasonality of influenza. All of these factors point to the value of taking a daily vitamin D supplement to ensure optimal vitamin D intake.

For those who need to take very high doses of vitamin D3 and are under a physician’s supervision, Life Extension offers a 5000 IU vitamin D3 supplement.