— found that those with normal body weight who took vitamin D experienced a 42 percent reduction in their risk of cancer death. The clinical trial lasted more than 5 years and involved about 26,000 middle-aged and older men and women., researchers were not able to draw conclusions on specific cancers, just on the risk of any type of cancer fatality, says Mason, the project’s lead investigator.
As for how much vitamin D people need to reduce risk, there isn’t evidence that high levels are better than moderate levels, she says. “We know it’s important to have adequate vitamin D levels in terms of bone health and cardiovascular function. Some is good but more is not necessarily better.” Plus, too much vitamin D can lead to elevated calcium levels in the blood and kidney stones.We can get vitamin D from food, but it’s minimal compared to what we can get from the sun.