The effects of spinach-derived thylakoid supplementation in combination with calorie restriction on anthropometric parameters and metabolic profiles in obese women with polycystic ovary syndrome: a randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND

There is a promising outlook regarding the potential effect of spinach-derived thylakoids in the management of obesity and its associated metabolic disturbances. This research aimed to evaluate the effects of spinach-derived thylakoids supplementation combined with a calorie-restricted diet on anthropometric and metabolic profiles in obese women with the polycystic ovary syndrome (PCOS).

METHODS

In a 12-week double-blind placebo-controlled randomized clinical trial, 48 females with obesity and PCOS were randomly allocated into either intervention (5 g/day thylakoid) or placebo (5 g/day cornstarch) groups along with calorie-restricted diets. Anthropometric measures, physical activity levels, dietary intakes, insulin resistance markers, as well as serum levels of insulin, fasting blood glucose (FBG), non-esterified fatty acids (NEFA), and sex hormones including dehydroepiandrosterone sulfate (DHEAS), follicle-stimulating hormone (FSH), luteinizing hormone (LH), sex hormone-binding globulin (SHBG), and free androgen index (FAI) were evaluated pre-and post-intervention.

RESULTS

After the 12-week intervention, there were significant decreases in weight (- 6.97 ± 0.52 vs. -3.19 ± 0.72 kg; P < 0.001), waist circumference (- 7.78 ± 2.50 vs. -3.73 ± 1.40 cm; P < 0.001), fat mass (- 5.19 ± 0.53 vs. -1.36 ± 0.39 kg; P < 0.001), and insulin levels (- 5.40 ± 1.86 vs. -1.19 ± 0.85 μU/mL; P < 0.001) in the spinach-derived thylakoid group compared to the placebo group. Furthermore, insulin resistance markers and serum levels of testosterone decreased significantly in the thylakoid group compared to the placebo group (P < 0.05). The changes in other parameters did not show significant differences between the two groups.

CONCLUSIONS

Spinach-derived thylakoid supplementation resulted in more favorable improvements in anthropometric indices and insulin sensitivity compared to the calorie restriction alone.

TRIAL REGISTRATION

The study was approved by the Ethics Committee of Research Vice-chancellor of Tabriz University of Medical Sciences, Tabriz, Iran, and was registered in the Iranian Registry of Clinical Trials (registration ID: IRCT20140907019082N9 ).