Meta-analysis links increased magnesium intake with fasting glucose and insulin reductions...

"Evidence from cross-sectional and longitudinal observational studies suggests that diets higher in magnesium are associated with reduced risk of insulin resistance and type 2 diabetes, whereas in intervention studies, supplemental magnesium improves measures of glucose and insulin metabolism in generally healthy adults, as well as in those with insulin resistance and type 2 diabetes," Adela Hruby and colleagues write. "However, little is known about potential interaction between magnesium intake and genetic variability on glycemic traits, in which genetic variants related to either magnesium transport and homeostasis or glucose and insulin metabolism may modify the pathways through which magnesium exerts its effects."

The researchers analyzed data from up to 52,684 nondiabetic men and women who participated in 15 studies included in the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium. Dietary questionnaire or interview responses, or food diary entries were analyzed for magnesium content from food and beverages. Participants were genotyped for up to 25 single nucleotide polymorphisms related to fasting glucose, insulin or magnesium.  Average magnesium intake ranged from 224.7 milligrams to 479.7 milligrams per day. Reductions in both fasting glucose and fasting insulin were observed in association with increased magnesium. While a nominal association was found between one of the genetic variants examined in this study and fasting glucose and two variants showed nominal interactions with magnesium intake on fasting glucose and fasting insulin, no significant effects for the variations were observed......... 

Ref : http://jn.nutrition.org/content/early/2013/01/22/jn.112.172049.abstract?sid=0219d7a7-cc12-4709-8167-805f0663e750

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