Nutritional and oxidative status in occupational obese subjects

Nutritional status, referred to meat and vegetable food consumption, is related to folate and B12 vitamin levels; hyperhomocysteinemia (HHcy) is due to folate and B12 vitamin-methionine metabolism imbalance, which can lead to oxidative stress, OS (imbalance between reactive oxygen species, ROS, and total antioxidant capacity, TAC). Possible early vitamin B12 (B12) deficiency can be highlighted by holotranscobalamin (HoloTC, bioactive cobalamin fraction) assay. Erythrocyte folate is a biomarker of 2- to 3-month folate storage. To evaluate nutritional status and OS we conducted an observational study on 118 occupational obese subjects (34M/84F, aged 16-69, median 46.5 years; BMI 26.5-54.1, median 33.3 kg/m2) without previous cardiovascular disease. Serum TAC and ROS (spectrophotometry, Diacron International, Italy), serum B12 and HoloTC, serum and erythrocyte folate, plasma Hcy (immunoenzymatic, AxSYM, Abbott Diagnostics, USA), lipid panel and inflammatory parameters by routine methods. All subjects showed adequate serum and erythrocyte folate levels, but HoloTC values revealed cobalamin deficiency in 30% of cases not congruent with B 12 concentrations, low only in 10%. 43% of cases showed mild HHcy (>10.5 μmol/L; median 12.44 μmol/L, IQR 11.2-16.2). OS was found by normal mean TAC values (370.5 micromolHClO/mL, 340-405; n.v. > 350) but increased mean ROS concentrations (386 CarrU, 337-434; n.v. 250-300) in 93% of subjects. Normal folate and B12 vitamin levels revealed a good nutritional status in our occupational obese subjects. The presence of Oxidative Stress, due to imbalance between ROS and TAC and mild hyperhomocysteinemia may heighten the obesity-related cardiovascular risk. © 2010 Springer-Verlag.