Which vitamin has a protective effect against colon cancer?

Which vitamin has a protective effect against colon cancer?
A . Vitamin C
B . Vitamin D
C . Folic acid
D . Vitamin K

View Answer

Answer: B

Explanation:

Calcium and vitamin D Calcium may protect against bowel cancer, according to the World Cancer Research Fund. A 2004meta analysis showed that people with the highest levels of calcium intake (from food and supplements) reduced their risk of bowel cancer by 22% compared to people with the lowest calcium intake.

However, 2 meta analyses in 2010 found that calcium supplements had no effect on bowel cancer risk in the general population. But they did find a link between calcium intake and a reduced risk of polyps coming back in the bowel after previous treatment. Polyps are growths in the bowel that may develop into cancer over a long period of time, if left untreated. To reduce bowel cancer risk, it may be better to take vitamin D and calcium together. We need vitamin D to be able to absorb calcium. A large randomized controlled trial in 2006 showed that only the people with high intakes of both calcium and vitamin D had a reduced risk of bowel cancer. Other studies have shown that people with the highest intakes of vitamin D have a lower risk of bowel cancer and bowel polyps. Dairy There is some evidence that drinking milk reduces the risk of bowel cancer. A review in 2011 showed that the benefit of dairy in reducing bowel cancer risk was only seen at levels over 100 grams (g) a day. Having 500 to 800g milk a day reduced bowel cancer risk by 20 to 30%. One pint, or 0.5 liters, of semi skimmed milk weighs about 550g. The effect of milk on lowering bowel cancer risk may be partly due to the calcium. But milk contains many other substances which may also play a role. There is limited evidence that eating cheese may increase the risk of bowel cancer. It is not clear how cheese may increase the risk, but it may have something to do with the saturated fatty acids.