Metabolic syndrome (MetS) features central obesity, dyslipidemia, insulin resistance, and hypertension, which predispose to cardiovascular disease (CVD), type 2 diabetes, and polycystic ovarian syndrome (PCOS). MetS and PCOS are intertwined, and patients may struggle with infertility, menstrual irregularity, weight, hirsutism, acne, and other symptoms. MetS and related conditions are addressed with diet, lifestyle, medications, and/or supplements.
Studies have shown that garlic addresses the overlapping pathogenic mechanisms of MetS and PCOS. Bioactive compounds in garlic, including allicin, can impact oxidative stress, apoptosis, inflammation, and vascular remodeling. A 2023 systematic review and meta-analysis of 19 RCTs concluded that garlic favorably impacts MetS variables, including serum lipids, blood pressure, and body composition.
Another 2023 systematic review revealed that garlic regulates hormones, enhances fertility, regulates the menstrual cycle, and reduces inflammation in the female reproductive system. A new study shows garlic’s benefit on components of MetS, symptoms, and quality of life (QOL) in women with PCOS.
The Study
A double-blind, randomized, controlled trial (RCT) included 97 women diagnosed with both PCOS and MetS. The mean patient age was around 32 years +/- 6 years. Participants received either garlic tablets (500 mg containing 2-3 mg allicin) or placebo twice daily for 8 weeks.
Fasting blood glucose, lipids, total testosterone (TT), sex hormone binding globulin (SHBG), and C-reactive protein (CRP) were assessed at baseline and at week 8. Weight, waist circumference (WC), hip circumference (HC), and blood pressure were measured. Female sexual function and QOL were evaluated using the female sexual function index (FSFI) and the modified polycystic ovary syndrome health-related quality of life questionnaire (MPCOSQ).
Compared to the placebo group, the garlic group showed several improvements:
- Body Composition: There was a significant reduction in weight, body mass index (BMI), WC, HC, and systolic and diastolic blood pressure. Waist-to-hip ratio did not differ between groups.
- Serum Labs: There was a statistically significant reduction in fasting blood glucose, LDL-C, total cholesterol, and CRP, as well as an increase in SHBG levels. A decrease in TT and an increase in HDL-C were not significant.
- Sexual Function: Significant improvements were observed in all six domains of the FSFI, including desire, arousal, lubrication, orgasm, satisfaction, and pain.
- Quality of Life: Significant QOL improvements were seen with the MPCOSQ, including hirsutism, acne, weight, infertility, menstrual, and emotional changes. (Note, the questionnaire does not directly assess infertility, but rather the emotional burden surrounding the inability to conceive and its effect on QOL.)
Conclusions
Garlic supplementation may be a safe, effective way to manage MetS markers in women with PCOS. Hormonal and cardiometabolic improvements are thought to contribute to improved symptoms, sexual function, and overall well-being. Although homocysteine (HCy) was not measured in this study, aged garlic extract has been shown to reduce levels by up to 30%. HCy correlates with elevated androgens in women with PCOS, particularly in the presence of obesity and insulin resistance. Elevated Hcy is strongly linked to CVD, menstrual, and fertility problems. By acting on multiple underlying mechanisms, garlic may offer multifactorial benefits in the treatment of PCOS.
