(P27-036-24) Differences Between Gastrointestinal Microbial Methane Producers vs Non-Producers and Consumption of Carbohydrates, Protein, Fat and Polyols

Objectives: The primary aim was to determine if differences exist between gastrointestinal microbial methane (CH4) production and dietary intake of carbohydrates (CHO), protein (PRO), fats, and polyols in a healthy population. We hypothesized there were differences in dietary intake of these nutrients in CH4 producers vs non-producers.

Methods: Adults consuming either a plant- or animal-based diet were recruited to complete a cross-sectional study. The Diet History Questionnaire III evaluated dietary intake over the past 3 months. The Quintron Breath Analyzer, a gold standard for breath testing, was used to analyze breath samples. Subjects completed a 12-hour fast prior to testing. Samples were collected in specialized single-use breath collection bags and injected into the Quintron. This machine measures once in triplicate at the time of visit and displays concentrations of hydrogen, CH4 and carbon dioxide in the breath. Subjects were classified into positive CH4 producers (PMP; CH4 ≥3 ppm) or negative CH4 producers (NMP; CH4 ﹤3 ppm). The primary aim was analyzed using MANOVA and univariate t-tests; Spearman correlations were also performed.

Results: The sample (n=55, 20.7±2.1 years) was primarily female (83.6%). The PMP group had an average CH4 value of 15.2±16.7ppm, while the NMP group had an average of 1.0±0.7ppm. The PMP group had an average CHO, PRO, fat, and polyol intake of 194.1±78.0g, 59.0±92.4g, 60.1±30.0g and 1.1±0.9g, respectively. The NMP group had an average CHO, PRO, fat, and polyol intake of 220.1±81.3g, 78.5±32.7g, 67.5±26.8g, and 0.9±0.5g, respectively. No significant differences were found amongst groups and intake of these nutrients via MANOVA. There was a significant difference in total PRO intake between PMP and NMP via univariate t-test (p=0.02), however, there were no significant differences in animal or vegetable PRO intake. CH4 output was negatively correlated with animal PRO (-0.3, p< 0.05).

Conclusions: CH4 production was not associated with differences in CHO, fats, and polyols; total PRO intake exhibited significant differences between producers and non-producers. Methanogen presence in the gastrointestinal environment may account for these differences; more work is needed to further discern nutritional impacts on gut microbial balance.

Funding Sources: University of Rhode Island, Undergraduate Research and Innovations Grant