Last summer, I told you about Dr. Edward Giovannucci, a noted Harvard Medical School professor and one of conventional medicine"s more outspoken proponents of healthy, natural vitamin D production via sunshine. Dr. Giovannucci"s latest paper highlights more recent findings that the sunshine vitamin also reduces a patient"s risks of colon cancer

Because a patient"s typical dietary intake (200-400 IUs per day) may be too low, daily exposure to sunshine increases one"s natural production of vitamin D and offer more protection from colon cancer. But higher nutritional intake of vitamin D may be required if one"s sun exposure is low.

And, with the full force of winter putting Americans from North Dakota to Texas in the deep freeze, spending any time outdoors is probably the last thing on your mind right now. Your best nutritional source of vitamin D during the winter months is a high-quality cod liver oil.

One reminder: It"s a good idea to have your vitamin D levels tested too.

Current Opinion in Gastroenterology, Vol. 22, No. 1, January 2006: 24-29