According to the American Council of Exercise, overweight people have, on average, greater than 30% body fat. In graph B, what do you notice about the amounts of hydrogen and methane in subjects with healthy body fat percentage compared to subjects who were overweight?

Subjects in the “normal” group had a normal amount of hydrogen, 20 ppm  or less, and a normal amount of methane, 3 ppm or less.   If subjects had greater amounts than the normal amount of hydrogen (≥20 ppm) detected but had less than the normal amount of methane (≤3 ppm), they were considered hydrogen positive (represented by the “Hydrogen Only” bar), while ≥3 ppm of methane detected but ≤20 ppm of hydrogen was considered methane positive (represented by the “Methane Only” bar).  If subjects had greater than the normal amounts of both gases (≥20 ppm of hydrogen and ≥3 ppm), they were considered hydrogen and methane positive (represented by the “Methane and Hydrogen” bar).

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