Medicine 101 – Dr. Tara Macart
Four separate studies in the last 3 months showed Vitamin D to have a protective effect against cancer. A four year clinical trial studying over 1000 women showed at least a 60 % reduction in the incidence of cancer in those who took a vitamin D supplement. For pennies a day, you too can reduce your risk.
After years of downplaying the role of vitamins and minerals, the Canadian Cancer Society has come out and endorsed 1000 IU per day of Vitamin D as preventative against cancer. This is an eyebrow raising recommendation because 1000 IU per day is five times the established recommended daily allowance (RDA).
This dosage recommendation is specific for the fall and winter, when vitamin D synthesis from sunlight exposure is less. Even though we also get Vitamin D from the diet, supplements are required to get enough to have the proposed anticancer effect. Dr. Vieth PhD, a researcher studying this vitamin, says people could take even more without danger of overdose. He suggests 1500 IU per day. This suggests that a multivitamin alone is insufficient.
Other than nutritional supplements, where do we normally get Vitamin D? In the diet, Vitamin D comes largely from animal products like eggs, meat, and fortified dairy products. Vegans can get it from mushrooms and fortified soy products. Vitamin D is synthesized in the skin with the help of sunlight. Fifteen minutes of sunlight on the skin three times a week has been suggested as a good amount, but it is difficult to standardize. Sunny weather is less in the northern latitudes than at the equator, and cloud cover is hard to factor in.
Since we are supposed to convert the inactive form of vitamin D into the active form with ultra-violet light in the summer, what about sunscreen? Sunscreens SPF 8 or higher effectively blocks Vitamin D production. The cancer society is rethinking its recommendation to use sunscreens in light of the latest findings. Compared to skin cancer, most of which are not lethal, more people suffer from cancers of the breast, colon, lung, prostate, and lymphoma combined.
Low Vitamin D Status has been linked to other diseases such as multiple sclerosis, juvenile diabetes, influenza, psoriasis and osteoporosis. This Vitamin D issue illustrates what orthomolecular doctors call a “relative vitamin deficiency”. People who take cholesterol lowering drugs or antacids could have low Vitamin D status because these drugs interfere with Vitamin D absorption.
There are several proposed mechanisms of action. One is the inhibition of the development of a blood supply to tumors. Another of note is that vitamin D increases absorption of calcium from the intestines. Cancer flourishes in acidic environments. We know calcium acts as a buffer in the body and it helps control acidity, thereby making a cancer cell’s physical environment less favorable for growth. Calcium supplements were shown to reduce the occurrence of colon cancer. It is debatable whether it is the vitamin or the calcium that has the protective effect. Could it be both?