Magnesium may reduce colon cancer risk: Meta-analysis

Increased intakes of magnesium may reduce the risk of developing colon cancer, says a new meta-analysis of data from 338,979 people.

Findings published in the European Journal of Clinical Nutrition indicated that for every 50 mg per day increase in intake of the mineral, the risk of colon cancer was modestly reduced by 7%.

“On the basis of the findings of this meta-analysis, a higher magnesium intake seems to be associated with a modest reduction in the risk of colorectal cancer, in particular, colon cancer,” wrote researchers from Soochow University in China.

Diet

Dietary sources of magnesium include green, leafy vegetables, meats, starches, grains and nuts, and milk. Earlier dietary surveys show that a large portion of adults does not meet the RDA for magnesium (320 mg per day for women and 420 mg per day for men).

Recently, scientists from the Karolinska Institutet in Stockholm, Sweden reported that, data pooled from seven prospective studies revealed that, for every 100 mg per day increase in magnesium intake, the risk of stroke was reduced by about 9% (American Journal of Clinical Nutrition).

In addition, a meta-analysis by scientists from Imperial College London and Wageningen University indicated that for every 100 milligram increase in intake of the mineral, the risk of colorectal cancer decreased by 12% (American Journal of Clinical Nutrition, doi: 10.3945/ajcn.111.030924).

Study details

For the new study, the Chinese researchers analyzed data from eight prospective studies containing 338,979 participants. Data was available for 8,000 cases of colorectal cancer.

Results indicated that the highest average intakes of magnesium were associated with an 11% reduction in the risk of colorectal cancer, compared with the lowest average intakes.

When the analysis was restricted to the six studies that adjusted for calcium intake, the results showed that the risks of colon and rectal cancer were 19% and 6% lower, respectively, for the highest average magnesium intakes.

The researchers said that they did not detect any publication bias.

Source: European Journal of Clinical Nutrition
Published online ahead of print, doi: 10.1038/ejcn.2012.135
“Magnesium intake and risk of colorectal cancer: a meta-analysis of prospective studies”
Authors: G-C Chen, Z Pang and Q-F Liu