Methane producing status increases serum acetate and lipids in subjects with impaired glucose tolerance

To determine if methane producers (MP) have a higher post-prandial serum ac etate concentrations over a 12-hour period than methane nonproducers (MNP) in subjects with impaired glucose tolerance (IGT), we studied 19 subjects: 11 MP and 8 MNP. Breath gases, hydrogen and methane, fasting serum total an d high-density lipoprotein (HDL) cholesterol and triacylglycerol were measu red. Plasma glucose and insulin and serum short chain fatty acid concentrat ions were measured fasting and over a 12-hour period. MP had significantly greater fasting serum total cholesterol (6.5+/-0.3 vs 5.4+/-0.3 mmol/L; P = 0.01) and LDL cholesterol (4.2+/-0.3 vs 3.0+/-0.4 mmol/L; P = 0.04) concen trations than MNP. No differences in TG or HDL cholesterol concentrations w ere observed. The mean 5-12 hour incremental area in serum acetate in MP wa s significantly higher compared to MNP (299.4+/-37.2 vs 151.3+/-47.6 mu mol /L; P = 0.02). From these results we can conclude that in IGT subjects, a p ositive methane producing status increases post-prandial serum acetate whic h may contribute to the increased serum total cholesterol concentration. (C ) 1999 Elsevier Science Inc.