Introduction: Research into the health effects of cocoa has received much attention over the past few years. Several systematic reviews and meta-analyses of existing studies have generally agreed on a potentially beneficial association between chocolate consumption and risk for cardiometabolic disorders. However, evidence regarding a potential role of chocolate consumption in insulin resistance and hepatic biomarkers, from human epidemiological studies, is lacking.

Hypothesis: We assessed the hypothesis that daily chocolate consumption would be inversely associated with insulin resistance and hepatic biomarkers in appraently healthy adults.

Methods: A random sample of 1153 individuals, aged 18-69 years, was recruited between 2007 and 2009 to participate in the Observation of Cardiovascular Risk Factors (ORISCAV-LUX) study. Chocolate consumption in g/day was obtained from a semi-quantitative food-frequency questionnaire. Blood glucose and insulin were used for the homeostasis model assessment of insulin resistance (HOMA-IR). Hepatic biomarkers, namely serum γ-glutamyl-transpeptidase (γ-GT), serum Aspartate Transaminase (AST) and serum Alanine Transaminase (ALT) in mg/l were assessed using standard laboratory assays.

Results: Chocolate consumers (81.8 %) were more likely to be younger, physically active, affluent people with higher education levels and have fewer chronic comorbidities. After exclusion of subjects taking antidiabetic medications, higher chocolate consumption was associated with lower HOMA-IR (β= -0.16, P=0.004), serum insulin levels (β= -0.16, P=0.003), and liver enzymes, including γGT (β= -0.12, P=0.009) and ALT (β= -0.09, P=0.004) after adjustment for age, sex, education, lifestyle (smoking status and physical activity) and dietary confounding factors, including daily energy intake, consumption of fruit and vegetables, alcohol, as well as polyphenol-rich coffee, and tea.

Conclusion: This is the first population-based study reporting an independent inverse relationship between daily chocolate consumption and levels of insulin, HOMA-IR and liver enzymes in adults.. Small dietary changes with respect to chocolate consumption may improve liver enzymes and protect against insulin resistance, a well-established risk factor for cardiometabolic disorders.