ABSTRACT
BACKGROUND: This study aims to investigate the nutritional status of vitamin A (VA) using biochemical and functional indicators in subjects with class III obesity, before and after RYGB, supplemented with three protocols. METHODS: The sample comprised 90 patients, with BMI ≥40 kg/m(2), divided into three groups: G1 that received routine supplementation containing 5,000 IU of retinol daily; G2 that received 10,000 IU of retinol daily; and G3 that received routine supplementation plus complementary of 50,000 IU of retinol intramuscularly every month. The status of VA was evaluated before (T0), 30 days (T1), and 180 days (T2) after surgery. RESULTS: The vitamin A deficiency (VAD) in G1, G2, and G3 was respectively 20.7, 21.2, and 20.2 % as regards retinol and 37.8, 63.3, and 40 % as regards ß-carotene in T0; 26.7, 10, and 23.4 % as regards retinol and 68, 37, and 32 % as regards ß-carotene in T1; and 21, 8.7, and 20.2 % as regards retinol and 63.3, 20, and 32 % as regards ß-carotene in T2. A reduction of retinol and ß-carotene with increasing BMI and waist circumference was observed in T0. The prevalence of night blindness (XN) in groups 1, 2, and 3 was respectively 23.3, 26.7, and 16.7 % in T0; 56.7, 40, and 60 % in T1; and 70, 43, and 63.3 % in T2. CONCLUSION: The study showed high prevalence of VAD. Among the supplementation protocols used, the one containing 10,000 IU of retinol showed the best impact. However, in cases of more severe VAD, intramuscular supplementation should be considered. The prevalence of XN, justifies attention to this segment of population.