Vitamin D3 may improve survival among older women, particularly those who are institutionalized, according to a meta-analysis published in the Cochrane Review.
MedPage Today reported that “Investigators found that “the supplement was associated with a 6% lower risk of death over an average follow up of two years, although when given in combination with calcium increased the risk of kidney stones.”

However, “other forms of vitamin D – vitamin D2, as well as the active metabolites alfacalcidol and calcitriol – had no effects on mortality.”
Although researchers have largely accepted mounting evidence that vitamin D plays a key role in bone health and forestalls falls and fractures, debate rages over whether supplementation can decrease the risk of non-skeletal problems including heart disease, cancer, and death.
They also found that supplementation was particularly beneficial for patients who were vitamin D deficient to begin with.
Also, doses below 800 IU a day – the recommended by the Institute of Medicine for patients over 70 – significantly decreased mortality (RR 0.92, 95% CI 0.87 to 0.97, P=0.005), while higher doses did not.

FYI, here’s my current protocol for testing and supplementing vitamin D:
I offer a 25-hydroxy vitamin D (25OH vit D) blood test for ALL patients during their preventive medicine exams – including teens and young adults. If the 25OH vit D level is below 30, the patient may either:

1.  Take a prescription tablet (Drisdol) containing 50,000 IU of vitamin D2 weekly for 12 weeks, or
2.  Take 2000 – 4000 IU of over-the-counter vitamin D3 daily for 12 weeks,

Then, I recheck the level, aiming for a level above 30.
Here are some of my recent blogs on vitamin D:

• Which vitamin D supplement boosts levels best — D2 or D3?
• Problems discovered with some vitamin D supplements
• Vitamin D Insufficiency: Is there enough evidence for clinical recommendations?
• What to do with the two new vitamin D guidelines?