Objective<b>: </b>To
examine the association between manganese intake and the risk of type 2
diabetes in postmenopausal women and determine whether this association is
mediated by circulating markers of inflammation.
<p>Research Design and
Methods: We included 84,285 postmenopausal women without history of
diabetes from the national Women’s Health Initiative Observational Study
(WHI-OS). Replication analysis was then conducted among 62,338 women
participated in the WHI-Clinical Trial (WHI-CT). Additionally, data from a
case-control study of 3,749 women nested in the WHI-OS with information on
biomarkers of inflammation and endothelial dysfunction were examined using
mediation analysis to determine the relative contributions of these known
biomarkers by which manganese affect T2D risk.</p>
<p>Results: Compared with the lowest quintile of
energy-adjusted dietary manganese, WHI-OS participants in the highest quintile
had a 30% lower risk of type 2 diabetes
(hazards ratio [HR] 0.70 [95% CI 0.65, 0.76]). A consistent association was
also confirmed in the WHI-CT (HR
0.79 [95% CI 0.73, 0.85]). In the
nested case-control study, higher energy-adjusted dietary manganese was
associated with lower circulating levels of inflammatory biomarkers that
significantly mediated the association between dietary manganese and type 2
diabetes risk. Specifically, 19% and 12% of type 2 diabetes risk due to
manganese were mediated through interleukin 6 and high-sensitivity C-reactive
protein, respectively.</p>
<p>Conclusions: Higher
intake of manganese was directly associated with a lower type 2 diabetes risk
independent of known risk factors. This association may be partially mediated
by inflammatory biomarkers.</p>
Influence of obesity, parental history of diabetes, and genes in type 2 diabetes: A case-control study
