Vitamin D levels and the risk of colon cancer
Researchers at the International Agency for Research on Cancer (IARC, in Lyon, France) and Imperial College of London, UK report a significant reduction in risk.
First, the details.
- The study was conducted within the EPIC study, a cohort of more than 520 000 participants from 10 western European countries.
- 1248 cases of colorectal cancer developed after enrollment and were matched to 1248 cases with no colorectal cancer.
- Circulating vitamin D concentration (25-hydroxy-vitamin-D, 25-(OH)D) was measured by enzyme immunoassay.
- Dietary and lifestyle data were obtained from questionnaires.
- Adjustments were made for potential dietary and other confounding factors.
And, the results.
- Lower blood levels of vitamin D showed a significant dose-related association with a higher risk of colorectal cancer.
- Patients with the highest vitamin D blood levels had a 40% lower risk of colorectal cancer vs those with the lowest vitamin D levels.
- There was no association with vitamin D levels and the risk of rectal cancer.
- Greater dietary intake of calcium was associated with a lower colorectal cancer risk.
- Dietary vitamin D was not associated with disease risk.
- Findings did not vary by gender and were not affected by corrections for season or month of blood donation.
The bottom line?
So, there’s an association between higher blood levels of vitamin D and lower risk of colon (but not rectal) cancer.
The researchers believe that future research should be designed to determine whether increasing circulating vitamin D concentrations might decrease the risk of colorectal cancer.
Thoughts on how vitamin D might protect from colon cancer are summarized here.
A study on the relationship between vitamin D and rectal cancer is summarized here.
5/11/10 18:53 JR
