Higher vitamin D levels may be linked to lower risk of bowel cancer
People with higher levels of vitamin D appear to be significantly less likely to develop bowel cancer, a new European study has found.
Researchers from a number of institutes in Europe, including Imperial College London, analysed data contained in the European Prospective Investigation into Cancer (EPIC) study, which involved over 520,000 people in ten countries.
Participants provided blood samples and information on their diet and lifestyle between 1992 and 1998, before being followed for several years.
At the time of the analysis, information from 1,248 people who had been diagnosed with bowel cancer was compared with information on 1,248 healthy controls also involved in the study.
The researchers discovered that people with the highest concentrations of vitamin D in their blood had a 40 per cent reduced risk of bowel cancer compared with those recording the lowest levels of the vitamin.
Writing in the British Medical Journal, the researchers concluded that vitamin D may be associated with a protective effect against bowel cancer.
However, they noted that insufficient research has been carried out into the long-term health impact of having high levels of vitamin D in the blood and that further research is needed both to confirm any beneficial effect on bowel cancer risk and to rule out any potential adverse effects.
Ed Yong, head of health evidence and information at Cancer Research UK, said: "This large study confirms that low levels of vitamin D are linked to an increased risk of bowel cancer. More research is needed to clarify whether vitamin D alone directly prevents this disease or if having higher levels of vitamin D means people are generally healthier.
"Either way, we know that vitamin D is important for good health," he continued.
"Enjoying the sun safely while taking care not to burn should help people strike a balance between making enough vitamin D and avoiding a higher risk of skin cancer. People can also top up their vitamin D levels by eating foods like oily fish (such as salmon, trout or mackerel), or by taking supplements after talking to their GP."
- Jenab, M. et al (2010). Association between pre-diagnostic circulating vitamin D concentration and risk of colorectal cancer in European populations:a nested case-control study BMJ, 340 (jan21 3) DOI: 10.1136/bmj.b5500