Instant coffee consumption may be associated with higher risk of metabolic syndrome in Korean adults

Aims: Cumulative evidence suggests that coffee consumption may have beneficial effects on metabolic diseases; however, few previous studies have considered the types of coffee consumed and the additives used. We investigated the relationship between coffee consumption and metabolic syndrome (MetSyn) and its components. Methods: We analyzed 17,953 Korean adults, aged 19-65 years, using cross-sectional data from the Korean National Health and Nutrition Examination Survey (KNHANES, 2007-2011). Coffee consumption level, types of coffee consumed, and the additives used were assessed based on a food frequency questionnaire and 24-h recall. Demographic and lifestyle factors were assessed using self-administered questionnaires. Data on metabolic biomarkers were obtained from a health examination. Multivariable logistic regression was used to determine the odds ratios of prevalent metabolic syndrome and its components according to frequency and type of coffee consumption. Results: We found that 76% of the subjects were habitual coffee drinkers, most of whom consumed instant coffee mix containing sugar and powder creamer. After multivariable adjustment, the odds ratios (95% CI) comparing those who consumed coffee ≥3 times/day with those who consumed coffee <1 time/week were 1.37 (1.15-1.63) for obesity, 1.33 (1.11-1.59) for abdominal obesity, 1.28 (1.09-1.51) for hypo-HDL cholesterolemia, and 1.37 (1.10-1.72) for metabolic syndrome. Instant-coffee drinkers were observed to have elevated risks of these metabolic conditions. Conclusions: Consumption of coffee, particularly instant coffee mix, may have harmful effects on MetSyn, perhaps partly deriving from excessive intake of sugar and powder creamer.