Sex-specific effects of the microbiota on adult carbohydrate intake and body composition in a polyphagous fly

•The microbiota, especially the gut microbiota, modulates host feeding, growth and fitness.•Removal of the microbiota (axenic) led to a sex-specific effect on host body weight, lipid reserves, and carbohydrate intake.•Axenic males were lighter, had lower lipid and lower carbohydrate intake than control and reinoculated males.•Axenic females had higher carbohydrate intake but lower fecundity than control and reinoculated females.•Our results reveal a sex-specific dynamic relationship between gut microbiota and the host.