Positive methane-producing status associated with increased serum cholesterol in subjects with impaired glucose tolerance.

To determine if those who produce methane (i.e., have presence of methane in breath) have higher serum cholesterol than those who do not produce methane in subjects with impaired glucose tolerance (IGT). We measured breath gases and fasting serum total and high-density lipoprotein (HDL) cholesterol and triglyceride (TG) levels in 21 subjects with IGT. The 11 methane-producers were well matched to the 10 non-methane-producers for age, sex, and body mass index. Methane-producers had higher fasting serum total (6.5 +/- 0.3 vs. 5.5 +/- 0.2 mmol/l; P < 0.02) and low-density lipoprotein (4.3 +/- 0.3 vs. 3.4 +/- 0.2 mmol/l; P < 0.05) cholesterol concentrations with no difference in TG or HDL levels. The results suggest that in subjects with IGT, positive methane-producing status may be associated with increased serum cholesterol levels.