Around this time of year, I start preaching to people about getting out of the sun to reduce their risk of skin cancer, particularly the deadly skin cancer called melanoma.

But sunshine, because it provides our bodies with vitamin D, is also good for us. A deficiency in this important vitamin has been associated with an increased risk of developing breast cancer, heart disease, and other forms of cancer. So what to do?

Do get out in the sun, but be smart about it and don't overdo. Wear sunblock. And to reduce your risk of sunburn, besides wearing sunblock, avoid going out between the hours of 10 a.m. and 2 p.m., when the UV rays are at their most intense.

I anticipate more research will be done in this area to better understand whether vitamin D slows the development of breast cancer.

If you suspect you're not getting enough vitamin D, ask your doctor to do a blood test to determine this because you won't necessarily have any symptoms telling you that your vitamin D levels are low. This is not a routine test; you must ask for it.

If you are deficient in vitamin D, you can purchase a supplement, but make sure it contains vitamin D3.