For some time we've known that vitamin D-primarily found in milk-is linked to a lower likelihood of developing colon cancer. But new scientific data suggests the vitamin may be a lifesaver even for those who already have the disease. Researchers at the Dana Farber Cancer Institute just released findings that colon cancer patients with higher levels of vitamin D in their blood were almost 50% less likely to die from any cause, and almost 40% less likely to die of colon cancer compared to colon cancer patients with vitamin D deficiency.
The protective effect of vitamin D is related to activation of the vitamin D receptor (VDR), which is known to inhibit the growth of malignant cells. Researchers speculate VDRs play a role in detoxifying a substance called lithocholic acid, a bile acid that is produced to help digest red meat and is thought to promote the development of colon cancer. Scientists are investigating the use of vitamin D supplements in treating and preventing colon cancer, but many agents are limited because excessive vitamin D intake can lead to dangerously high levels of calcium in the blood.
More studies are needed to determine whether vitamin D supplements should be routinely recommended for colon cancer patients, but deficiency should definitely be avoided. We get vitamin D in our diet, but we can actually make our own vitamin D with the help of sun exposure. Dark-skinned individuals are more likely to suffer from vitamin D deficiency because melanin impedes the penetration of sunlight into the skin. Vitamin D is found in fortified milk and butter, cod liver oil, salmon, sardines, and mackerel, and the recommended daily allowance is 200 International Units (IU) for people aged 19-50; 400 IUs for those between 51 and 69; and 600 IUs for those 70 years and older. Too much vitamin D can cause dehydration, nausea, constipation, weakness, so the Institute of Medicine's Food and Nutrition Board recommends an upper limit of 2,000 IUs of vitamin D for children and adults, and an upper limit of 1,000 IUs for infants under 12 months of age.
What's also important to remember is that while lung cancer is well recognized as the top killer malignancy, colon cancer is second in line in the US. More than 57,000 Americans die from colon cancer each year, but unlike most cases of lung cancer, colon cancer can be caught early with regular screening and is often curable at an early stage. In addition to maintaining adequate dietary intake of vitamin D, you should get your screening colonoscopy every 10 years starting at age 50. If you have a family history of colon cancer you should start at age 40, and if you've had colon polyps you should be checked every 3-5 years. For more information on colon cancer screening please refer to the following website: http://www.colonoscopy.info/download/flash.html