Background: The influence of weight loss treatment on sex hormones profile has been studied mainly in women with polycystic ovary syndrome (PCOS), but in obese premenopausal women without PCOS it still remains unclear. The aim of the study was to evaluate the effect of two approaches to obesity treatment on the serum level of sex hormones in obese women of child-bearing age without PCOS.
Methods: 77 obese Caucasian women (aged 31.2 ±8.3 years) were randomized into two groups: 39 women received a low-calorie diet (LC) and 38 received an isocaloric diet plus metformin (IM), for 12 weeks. Anthropometric parameters, body composition and serum concentrations of estradiol (E2), testosterone (T), follicle-stimulating hormone (FSH), luteinizing hormone (LH) and dehydroepiandrosterone (DHEA-S) sulfate were evaluated at baseline and after the study.
Results: Reductions in body weight, body mass index (BMI), waist and body fat content with an increase in lean body percent were significant and comparable between the LC and IM group after the trial. The concentrations of serum FSH, LH, E2, DHEA and T did not change in either group after treatment. A tendency towards an increase in the E2 concentration in both groups and a decrease in the T level in the LC group was observed. The correlations between a change in BMI, fat content, waist-hip ratio and a change in T were documented in the LC group.
Conclusions: A 12-week low-calorie diet and an isocaloric diet combined with metformin produced comparable and significant weight loss with improvements in body composition. Both interventions did not significantly affect FSH, LH and DHEA sulfate serum concentrations, only a trend towards an E2 increase and a T decrease was observed, stronger in LC group. The significant correlations shown between the changes in anthropometric and body composition parameters and T serum levels in women treated with a low-calorie diet alone show the beneficial effect of a lifestyle intervention on the sex hormone in obese premenopausal women.
Keywords: low-calorie diet; metformin; obesity; sex hormones.