Am J Clin Nutr. 2012 Sep;96(3):622-31.
Magnesium intake and colorectal tumor risk: a case-control study and meta-analysis.
Wark PA, Lau R, Norat T, Kampman E.
Source
Department of Epidemiology and Biostatistics, School of Public Health, Imperial
College London, London, UK. p.wark@imperial.ac.uk
Abstract
BACKGROUND:
Dietary magnesium might be related to colorectal tumor risk through the pivotal
roles of magnesium in cellular metabolism, insulin resistance, and systemic
inflammation.
OBJECTIVE:
We evaluated the hypothesis of whether higher dietary magnesium intake is
associated with reduced colorectal tumor risk.
DESIGN:
A case-control study on colorectal adenomas (768 cases; 709 polyp-free control
subjects) and a meta-analysis of colorectal adenomas (3 case-control studies)
and carcinomas (6 prospective cohort studies) were conducted. Dietary magnesium
was estimated from food-frequency questionnaires in the case-control study and
most studies in the meta-analyses. Data analysis comprised multiple logistic
regression analysis (case-control study) and fixed- and random-effects
meta-analyses.
RESULTS:
The case-control study showed a nonsignificant inverse association between
dietary magnesium intake and risk of colorectal adenomas (OR for every 100-mg/d
increase: 0.81; 95% CI: 0.62, 1.06). However, inverse associations were observed
only in subjects with BMI (in kg/mē) >=25, in subjects aged >=55 y, and for
advanced adenomas. Associations did not vary by the calcium-to-magnesium intake
ratio. In the meta-analysis, every 100-mg/d increase in magnesium intake was
associated with 13% lower risk of colorectal adenomas (OR: 0.87; 95% CI: 0.75,
1.00) and 12% lower risk of colorectal cancer (RR: 0.88; 95% CI: 0.81, 0.97).
CONCLUSIONS:
Our findings support the hypothesis that higher intakes of dietary magnesium are
associated with lower risk of colorectal tumors. The consumption of
magnesium-rich foods may be a new avenue to explore further in the search for
cancer-prevention strategies.
PMID: 22854408 [PubMed - indexed for MEDLINE]