Vitamin D Supplements or Sun Exposure?

Sun exposure is the easiest and most natural way to get vitamin D. In fact, exposure to sunlight provides most of us with all the vitamin D we need to meet our daily requirements. In brief, what happens is that the UV rays from the sun actually trigger vitamin D synthesis in our skin.

That said, many factors can limit our abilities to get vitamin D this way. Things like:

- The season of the year

- Your geographic latitude

- The time of day you are outside

- The cloud cover

- The amount of smog where you live

- Whether you are wearing sunscreen

Even bright sunlight exposure from November through February in Boston for example won't allow you to produce significant vitamin D, and you may have to take a D supplement

As far as sunscreens, anything with a sun protection factor (SPF) of 8 or greater will block the UV rays that produce vitamin D naturally (it is still vital to routinely use sunscreen to help prevent skin cancer and other negative effects of excessive sun exposure though). If your health care practitioner agrees, an initial exposure to sunlight (10 -15 minutes) allows for adequate time for Vitamin D synthesis to start. Then you can apply sunscreen.

So, what does all this mean? If you have limited sun exposure you may need vitamin d supplements.