OBJECTIVES To assess micronutrient variations in HIV/AIDS patients before and after HAART (highly active antiretroviral therapy). METHODS We evaluated the nutritional status and micronutrients in 44 patients over 3 years. The first nutritional evaluation was conducted in 1995 before HAART, the second was conducted in 1998 when most patients received HAART. RESULTS Thirty-four (77%) of the patients were intravenous drug users. In 1995, 35 (80%) were receiving antiretroviral therapy, but none had a protease inhibitor. A comparison made between patients in the group with CD4 <250/mm(3) (group A) and patients in the group with CD4 >250/mm(3)(group B) revealed significantly lower levels of plasma selenium concentrations (p < 0.05). In group A women, zinc was significantly lower than in men of the same group (p < 0.05). On the contrary, selenium plasma concentrations were significantly lower in group A men than in group A women (p < 0.05). No significant differences were noted for other micronutrients. In 1998, when most patients were treated with HAART, differences between the two groups were no more significant, neither for selenium nor for zinc matched with sex. Micronutrient values did not significantly differ between patients with viral load below 5,000 copies/ml and patients with viral load above 5,000 copies/ml. Patients treated with HAART had practically no weight loss. Although patients who did not receive HAART had a good immune status, the mean weight loss was up to 4.6 kg. CONCLUSIONS Selenium and zinc deficiencies are dependent on immune status and sex in HIV/AIDS patients. Other micronutrients do not seem to be influenced by the immune status in these patients. HAART reduces selenium and zinc deficiencies and may help avoid weight loss independently of the CD4 cell count.