text: can a hiv infected person gain weight? i used to have sex with prostitudes...but since last two and a half years i have not had sex...and in the last six months i have gained five kgs of weight. well i am a hiv+ person and have been for the last 12 years or so, and i have never had trouble either gaining weight or losing it. good nutrition is great for the body no matter if you have health issues or not. but since you are concerned in regards to hiv and you have taken part in higher risk sexual behavior my suggestion would be to have an hiv test performed. your local aso has a simple 15min test available.