Vitamin A supplementation, serum lipids, liver enzymes and C-reactive protein concentrations in obese women of reproductive age.

BACKGROUND: High-dose vitamin A influences glucose and lipid profile; however, the possible effects of moderate doses (25,000 IU/d) are conflicting. We aimed to compare the effect of vitamin A supplementation on several anthropometric and biochemical variables between obese and non-obese women.

METHODS: This study was performed on 84 women among whom 56 were obese (body mass index [BMI] 30-35 kg/m(2)) and 28 were non-obese (BMI 18.5-24.9 kg/m(2)). Obese women were randomly divided into two groups: one group received 25,000 IU/d retinyl palmitate and another group received placebo. The third group was age-matched non-obese women who received 25,000 IU/d retinyl palmitate. At baseline and four months after intervention, fasting blood glucose (FBG), lipid profile, C-reactive protein (CRP) and liver enzymes were evaluated.

RESULTS: Baseline concentrations of serum FBG and triglyceride in the obese vitamin A-treated group were significantly higher compared with the other groups (P = 0.004 and 0.007, respectively). A significant increase in serum FBG (P = 0.026), total cholesterol (TC) (P = 0.004) and low-density lipoprotein cholesterol (LDL-C) (P = 0.016) in the non-obese group and a significant decrease in serum high-density lipoprotein cholesterol (HDL-C) (P = 0.001) in the obese group was observed. Serum CRP increased significantly in the obese vitamin A-treated group (P = 0.03) and serum aspartate transaminase increased significantly in the obese and non-obese groups after vitamin A supplementation (P = 0.008 and 0.001, respectively).

CONCLUSIONS: Treatment with 25,000 IU/d vitamin A induced a mild elevation in serum lipids, CRP and liver enzymes in obese and non-obese women. Considering the other information about possible side-effects of excess vitamin A, use of vitamin A in this dose and duration should be considered with caution.