Moderate alcohol intake is associated with decreased risk of insulin resistance among individuals with vitamin D insufficiency.
OBJECTIVE
To determine whether moderate alcohol intake modifies the association between low vitamin D levels and insulin resistance (IR), we hypothesized that moderate alcohol intake would have a modifying effect on IR in people with low vitamin D levels.


METHODS
This was a cross-sectional analysis of subjects > or = 20 y old without a history of diabetes, coronary heart disease, or stroke in the National Health and Nutrition Examination Survey 2001-2004. Main outcome was IR status measured by homeostasis model assessment for IR (HOMA-IR; > or = 2.6) and fasting insulin (>12.2 microU/mL) in moderate drinkers compared with non-drinkers by vitamin D levels (deficient < or = 20 ng/mL, insufficient 21-32 ng/mL, normal >32 ng/mL).


RESULTS
Two thousand seven hundred twenty-one subjects met the inclusion criteria, representing a weighted total of >138 million people. Of these, 34% were vitamin D deficient and 47% insufficient. In adjusted analysis, compared with moderate drinkers with normal vitamin D levels, non-drinkers had no increased risk of IR by HOMA-IR levels (odds ratio [OR] 1.18, 95% confidence interval [CI] 0.61-2.30). Vitamin D-deficient individuals had a higher risk of IR regardless of alcohol consumption (moderate drinkers OR 2.12, 95% CI 1.41-3.19; non-drinkers OR 2.22, 95% CI 1.29-3.83). However, in those with insufficient vitamin D levels, moderate alcohol intake had a modifying effect on the odds of IR, with no difference seen in moderate drinkers (OR 1.29, 95% CI 0.92-1.80) and an increased risk found in non-drinkers (OR 1.82, 95% CI 1.07-3.11). Similar results were seen with fasting insulin.


CONCLUSIONS
Moderate alcohol consumption appears to have a modifying effect on the risk of IR in individuals with insufficient levels of vitamin D.
Player
Marty S
MS
Department of Family Medicine, Medical University of South Carolina, Charleston, South Carolina, USA. playerm@musc.edu
Mainous
Arch G
AG
King
Dana E
DE
Diaz
Vanessa A
VA
Everett
Charles J
CJ
D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000097:blood / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012016:Reference Values; D012307:Risk Factors; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications*; D055815:Young Adult
D007328:Insulin