Vitamin D3

Research is showing that vitamin D3 plays many roles in keeping our bodies healthy. As far as strength and balance are concerned it helps:

  • ensure that the body absorbs and retains calcium, which is needed for muscle function.
  • protect bone strength and prevent fractures, as well as falls from fractures that occur spontaneously from osteoporosis.
  • increase muscle strength, which in turn helps to prevent falls.

How much vitamin D3 should we take? According to an article published by the Harvard School of Public Health: “Researchers found that high intakes of vitamin D supplements – of about 800 IU per day – reduced hip and non-spine fractures by 20 percent, while lower intakes (400 IU or less) failed to offer any fracture prevention benefit.” As far as muscle strength, the article continues: “Once again, vitamin D dose matters: A combined analysis of multiple studies found that taking 700 to 1,000 IU of vitamin D per day lowered the risk of falls by 19 percent, but taking 200 to 600 IU per day did not offer any such protection.”

How do I know if I am getting enough vitamin D? According to Sarfraz Zaidi, MD in his book Power of Vitamin D, the right blood test to evaluate vitamin D status is 25 (OH) vitamin D, which is pronounced 25-hydroxy vitamin D.

What are is the normal range of vitamin D? According to Dr. Zaidi, “The normal ranges for vitamin D come from the era when our concern was just to prevent rickets. A small dose of vitamin D is enough to prevent rickets … That’s why many laboratories report 10 ng/ml (25 nmol/L) as the lower limit of the normal range.” He goes on to explain that we now know that vitamin D plays many important roles in the body in addition to preventing rickets. For this reason many experts in the field recommend that the lower level be at least 30 ng/ml (or 75 nmol/L, which are the units used by some labs) and preferably above 50 ng/ml (or 125 nmol/L, which are the units used by some labs).

If your vitamin D level is above 10 ng/ml, your doctor may tell you that your level is “normal” since it is within the normal limits set by the lab. But to be sure it is at least 30 ng/ml, it is a good idea to ask for the actual number or to get the lab report. Dr. Zaidi bases his starting dose of vitamin D supplement on how low your vitamin D is. For example, if your vitamin D level is more than 40 ng/ml, he may recommend you take 1000 IU of vitamin D3 per day, but if your level is less than 10 ng/ml, he may recommend 7000 IU per day. Of course, you should always check with your health care provider for recommendations based on your unique medical status.