In yet another study of vitamin D, Reuters is reporting a study where scientists found that low vitamin D levels are associated with a higher risk for heart attack. 
Researchers studied medical records and blood samples from 454 men aged 40-75 who had either died from heart disease or who were alive but had a heart attack.
Men with lower vitamin D levels were more likely to smoke, be less physically active, and weigh more than those who had higher levels. 
My Take?
The researchers, after adjusting for all known risk factors, found that men with low vitamin D had abut two and one-half times the risk for heart attack. 
The authors suggest that the dietary requirements for the vitamin may need to be reevaluated.
Readers of my blog know I recommend vitamin D and calcium supplements for adults, and vitamin D supplements for children. 
Vitamin D helps the body absorb calcium and is considered important for bone health. In adults, vitamin D and calcium prevents osteoporosis, and in children, they prevent rickets.
A number of recent studies have indicated vitamin D also may offer a variety of other health benefits, including protecting against macular degeration, muscle weakness and fall, several types of cancer, including colon and breast cancer, peripheral artery disease, and tuberculosis.
In January, researchers led by Dr. Thomas Wang of Harvard Medical School reported findings that fit with the new study, showing that people with low vitamin D levels have a higher risk for heart attack, heart failure, and stroke.
I think there is enough good evidence about the value of vitamin D to encourage people to ensure they have normal levels. You can learn you vitamin D level by having your doctor check it with a simple blood test. 
If your level is too low can, you can take a vitamin D supplements.
However, for those not wanting to spend this money, I think it’s fine for adults to take 400 – 800 IU of vitamin D per day and 600 – 1200 mg of calcium per day. These should be taken in divided doses and with food.
Be sure to check with your doctor about the dose, dosing frequency, and supplement he or she would recommend for you and your family.