Introduction The nutritional profile of HIV-infected patients after the introduction of HAART has pointed to high rates of overweight and obesity that have been associated with the emergence of long term co-morbidities, including metabolic changes.

Methods A cross-sectional nested case control study was conducted to estimate the prevalence of thinness and overweight/obesity and associated factors in 2018 individuals with HIV/AIDS, using the Body Mass Index (BMI). Thinness were classified as BMI<18.5 kg/m², overweight/obesity BMI≥25 kg/m² and eutrophic BMI≥18.5–24.9 kg/m². As the outcome variable has more than two levels we performed the multinomial logistic regression analyses comparing thinness and overweight/obesity to eutrophic as the reference level.

Results The prevalence of thinness was 8.8% and that of overweight/obesity 32.1%. The variables associated with thinness were anaemia and CD4 cell count <200 mm³. The risk factors for overweight/obesity were age ≥40 years and diabetes and the variables identified as protective factors for overweight/obesity were not having a long term partner, smoking, presence of an opportunistic disease, anaemia, and albumin levels <3.5 mg/dl.

Conclusion The main nutritional problem observed in this population was overweight and obesity, which were much more prevalent than thinness. Older individuals with diabetes should be targeted for nutritional interventions and lifestyle changes.