If you could take a pill that would reduce
your risk of developing breast or colon cancer in half, would you?
Research completed at several major universities over the past
few years suggests that vitamin D may an important part of any cancer
prevention program.
Vitamin
D was previously thought to have a small role in maintaining strong
and healthy bones, and alleviating depression.
However, the ‘sunshine vitamin’ appears to play a role in
prevention of many other diseases (including diabetes and high blood
pressure) and also in reducing cancer risk. In adults, vitamin D
deficiency can lead to bone loss, muscle weakness, fractures and
even common cancers, as well as autoimmune, infectious and
cardiovascular diseases. Nationwide, it is estimated that only 29
percent of the United States population has optimal levels of vitamin
D.
In
June 2006, Creighton University School of Medicine in Nebraska
reported results from a study which evaluated healthy menopausal women
for four years to determine if vitamin D and calcium or just calcium
alone could reduce the number of new cancer cases compared to a sugar
pill placebo. Of the
1,179 women who participated in the study, those who took the calcium
alone saw a 40 percent reduction in cancer rates compared to the sugar
pill. For women who took
both the calcium and the vitamin D, however, there was a dramatic 77
percent or greater reduction in cancer risk compared to women who took
the sugar pill.
In
August 2007, a research team from the University of California, San
Diego, reported that up to 50 percent of breast and colon
cancer cases could be prevented by consuming higher doses of vitamin D
on a daily basis. The
researchers found that supplementation with 2,000 international units
(IU) of vitamin D daily could reduce the risk of developing colon
cancer by 50 percent. The
amount of vitamin D needed to reduce the risk of breast cancer by 50
percent was higher at 3,500 IU daily.
The study found that the average adult intake of vitamin D in
the United States is 230 IU daily—well below the recommended daily
allowance of 400 IU. The
authors of the study assert that if all people in North America could
maintain vitamin D levels of 55ng/ml (nanograms per milliliter—the
unit of measure for vitamin D), approximately 60,000 cases of
colorectal cancer and up to 85,000 cases of breast cancer could be
avoided.
Vitamin D is
best obtained through judicious sun exposure.
Some of the leading researchers in the field of vitamin D
recommend 20 minutes of ‘unprotected’ sun exposure three times per
week during summer months. This limited sun exposure without suntan
lotions is particularly important to Alaskans, as Alaska has a short
summer. Foods that
contain vitamin D include cod liver oil, and small amounts can also be
found in egg yolks and butter.
Vitamin D
levels should be assessed before starting any vitamin D
supplementation. This is because vitamin D is fat soluble and could be
toxic in high doses. Your medical provider can test your vitamin D status by a
simple blood draw. The
test is called “25-hydroxy vitamin D” (often written as
25(OH)vitamin D). The
currently accepted optimal range for vitamin D is 60-80ng/ml.
Multiple studies have found that the largest beneficial impact
of reducing cancer risk is for those people with a 25(OH)vitamin D
level of at least 75ng/ml. If
your vitamin D level is significantly lower than the optimal range,
your medical provider may recommend higher doses of vitamin D for a
limited period of time to correct the deficiency.
Given
that proper vitamin D levels affect multiple aspects of our health,
testing for adequate vitamin D status and proper vitamin D intake
should become part of every disease prevention and wellness plan.
Dr.
Michelle Rogers is a Naturopathic Doctor practicing in Anchorage.
You may contact her at Avante Medical Center, 770-6700.
