Boosting levels
of vitamin D and calcium in post-menopausal women did not help them reduce
their breast cancer risk. This is the first real test on whether vitamin
D actually causes poor health as opposed to just being a marker for poor
health, and it failed. So far, we have a few good studies to show that
people with low vitamin D levels are more prone to illnesses such as cancer and
heart disease, but there is no evidence yet that giving people vitamin D
supplements will reduce their disease risk. In a study of more than
36,000 post-menopausal women, those taking vitamin D and calcium supplements
for seven years did not have any lower risk for breast cancer than those taking
a placebo. However, the door isn't closed on vitamin D and breast cancer
just yet. It is possible women need to take the supplements when they're
younger to get benefits, or perhaps they'll even need higher doses.
