Extrapolation of data from energy balance studies in HIV-seropositive men to HIV-seropositive women may be inaccurate due to gender differences in body composition, hormones and metabolism. If women have a different metabolic response to the human immunodeficiency virus (HIV), nutritional advice may differ from HIV-seropositive men. Ten asymptomatic HIV-seropositive women were matched with 10 heterosexual female controls from low-risk groups. Subjects and controls had assessment of energy and protein intake, resting energy expenditure (REE) and substrate oxidation, small bowel absorption and permeability and body composition. There were no significant differences in REE, substrate oxidation and body composition. Energy and protein intake and small bowel permeability were increased and sugar absorption decreased in HIV-seropositive women (all P < 0.05). Unlike asymptomatic HIV-seropositive men, asymptomatic HIV-seropositive women do not have significant alterations in metabolism or body composition. Therefore, nutritional advice may need to vary according to the gender of the asymptomatic HIV-seropositive subject.