Obesity is always a case of calories in vs calories out. Were they controlling an exact caloric difference? Also: This is on male mice, which experience topor,

Obesity is always a case of calories in vs calories out. Were they controlling an exact caloric difference? Also: This is on male mice, which experience topor, which means they can dial their metabolisms way back. Human metabolism just doesn't work like that. Studies have consistently shown that metabolism is pretty constant across the gamut of humans based on muscle mass, activity, and weight.