Mediterranean Diet Combined With a Low-Carbohydrate Dietary Pattern in the Treatment of Overweight Polycystic Ovary Syndrome Patients

Abstract

Objectives: To determine the therapeutic effect of a Mediterranean diet (MED) combined with a low-carbohydrate (LC) dietary model in overweight polycystic ovary syndrome (PCOS) patients.

Methods: In this 12-week randomized controlled clinical trial, 72 overweight patients with PCOS were randomly assigned to one of two energy-restricted dietary models: the MED/LC diet or the Low fat (LF) diet. After the intervention, the number of the two groups returned to normal menstruation was counted. Body weight, body mass index (BMI), waist circumference, waist-hip ratio (WHR), body fat percentage (BF%), serum fasting insulin(FINS), fasting plasma glucose(FPG), insulin resistance index (HOMA-IR), quantitative insulin sensitivity index (QUIKI), total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglyceride (TG), total testosterone (TT), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and prolactin (PRL) were compared between 2 groups before and after intervention.

Results: MED/LC group had more significant reduction trend in weight (-6.10 ± 1.52 kg vs -4.79 ± 0.97 kg, P < 0.05), BMI (-2.12 ± 0.57 kg/m² vs -1.78 ± 0.36 kg/m², P < 0.05), WC (-6.12 ± 5.95 cm vs -3.90 ± 1.58 cm, P < 0.05), WHR (-0.06 ± 0.02 vs -0.03 ± 0.02, P < 0.05), BF% (-2.97% ± 1.78% vs -1.19% ± 0.91%, P < 0.05), TT (-0.20 ± 0.24 ng/mL vs 0.08 ± 0.11 ng/Ml, P < 0.001), LH (-5.28 ± 3.31 mIU/mL vs -3.39 ± 3.64 mIU/mL, P < 0.05), and LH/FSH (-1.18 ± 0.75 vs -0.66 ± 1.05, P < 0.05) compared with the LF group. In addition, FPG (0.05 ± 0.38 mmol/mL vs -0.50 ± 1.01 mmol/mL, P < 0.001), FINS (-4.88 ± 6.11 μU/mL vs -8.53 ± 5.61 μU/mL, P < 0.01), HOMA-IR index (-1.11 ± 1.51 vs -2.23 ± 0.25, P < 0.05), and QUIKI index (0.014 ± 0.016 vs 0.028 ± 0.019, P < 0.05) decreased significantly in the MED/LC group compared with the LF group. Comparing the changes in lipid parameters between the two groups (LF vs MED/LC), significant differences in TG (-0.33 ± 0.32 mmol vs -0.76 ± 0.97 mmol, P < 0.05), TC (-0.40 ± 1.00 mmol vs -1.45 ± 2.00 mmol, P < 0.05), and LDL-C (-0.41 ± 1.05 mmol vs -0.73 ± 0.76 mmol, P < 0.05) were observed.

Conclusion: The results of this study suggest that the MED/LC diet model is a good treatment for overweight PCOS patients, significantly restoring their menstrual cycle, improving their anthropometric parameters and correcting their disturbed endocrine levels, and its overall effectiveness is significantly better than the LF diet model. Therefore, this study recommends that the MED/LC diet model can be used in the clinical treatment of patients with overweight PCOS.

Keywords: low-carbohydrate diet; mediterranean diet; overweight; overweight mediterranean diet; polycystic ovary syndrome.

FIGURE 1

Flow chart from the study design.

FIGURE 2

Intake of energy and nutrients between the diet intervention groups. (A) Baseline for daily total energy intake remained the same for both groups(P > 0.05). (B) The Mediterranean/low-carbohydrate (MED/LC) diet more greatly decreased the intake of carbohydrate and more greatly increased the intake of protein, fat and saturated fatty acids (SFAs). (C) No difference in daily cholesterol intake between the two groups(P > 0.05). Analysis of variance with a covariance (ANCOVA) test was used. LF, low fat diet.

FIGURE 3

Comparison of changes in anthropometric variables between two groups. (A) The MED/LC diet resulted in more weight loss than the LF diet. (B) MED/LC diet reduced body mass index (BMI) more than LF diet. (C) The MED/LC diet resulted in more waist circumference (WC) loss than the LF diet. (D) MED/LC diet reduced waist-to-hip ratio (WHR) more than LF diet. (E) The MED/LC diet resulted in more body fat percentage (BF%) loss than the LF diet. Data are mean (± SD). Analysis of variance with a covariance (ANCOVA) test was used.

FIGURE 4

Comparison of changes in serum sex hormone levels between two groups. (A) The MED/LC diet resulted in more total testosterone (TT) loss than the LF diet. (B) MED/LC diet reduced luteinizing hormone (LH) more than LF diet. (C) The MED/LC diet resulted in more ratio of luteinizing hormone to follicle-stimulating hormone (LH/FSH) loss than the LF diet. (D) Prolactin (PRL) changes of MED/LC diet and LF diet had no difference. Data are mean(±SD). Analysis of variance with a covariance (ANCOVA) test was used.

FIGURE 5

Comparison of changes in metabolic parameters between two groups. (A) Change in fasting plasma glucose (FPG) in the MED/LC diet compared to the LF diet. (B) Change in fasting insulin (FINS) in the MED/LC diet compared to the LF diet. (C) Change in homeostatic mode assessment of insulin resistance (HOMA-IR) in the MED/LC diet compared to the LF diet. (D) Change in quantitative insulin sensitivity check index (QUIKI) in the MED/LC diet compared to the LF diet. (E) Change in blood lipid level in the MED/LC diet compared to the LF diet. TC, total cholesterol; TG, triglyceride; HDL-C, high-density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol. Data are mean (± SD). Analysis of variance with a covariance (ANCOVA) test was used. *P < 0.05. ns: P > 0.05.