# Soy Isoflavones and PCOS: Role in Hormonal and Metabolic Mechanisms
## 4 Polycystic Ovary Syndrome and Soy Isoflavones
### Metabolic Mechanisms
#### 4.2.3 Lipid Profile and Cardiovascular Risk  
Metabolic abnormalities in PCOS--including obesity, IR, hepatic steatosis, and dyslipidemia--increase the risk of CVD, highlighting the systemic nature of PCOS-related complications. Dyslipidemia is more common in women with PCOS than in women without the condition, and according to some studies, it affects up to 50-70% of PCOS patients [168; 169]. In a meta-analysis by [PERSON] et al., women with PCOS were found to have significantly higher total cholesterol levels, lower levels of the HDL fraction, and an increased risk of hypertension, type 2 diabetes, and non-fatal cerebrovascular events [170]. Interestingly, women with PCOS without obesity are more likely to have adverse lipid abnormalities, such as hypertriglyceridemia and reduced HDL fraction cholesterol levels, compared to the control group [171]. This suggests that even in the absence of obesity, PCOS patients remain at increased risk of CVD. In addition to metabolic disorders, hyperandrogenism, which affects sympathetic nervous system activation and oxidative stress, may play an important role in the development of CVD. These may include the MC4R receptor pathway and arachidonic acid metabolites such as 20-HETE [172; 173; 174]. Soy isoflaves have been suggested to have a moderate protective effect against CVD risk factors. A recent meta-analysis by [PERSON] et al. showed that supplementation with isolated isoflaves can lead to a significant reduction in blood pressure, while [PERSON] and [PERSON] showed that consumption of soy protein containing isoflaves significantly improves lipid profile--lowering total cholesterol, LDL cholesterol, and triglycerides, and increasing HDL levels--which may contribute to CVD risk reduction [175; 176]. In addition, isoflaves may support endothelial function through antioxidant and anti-inflammatory effects, and increased nitric oxide production, an important mechanism in the prevention of atherosclerosis [177; 178]. In prospective studies, isoflave intake was inversely associated with all-cause and cancer-related mortality, although no significant association was confirmed for CVD mortality [18]. There is also growing interest in equal, the active metabolite of daidzein, which may have stronger cardioprotective effects than soy isoflaves alone [74; 179]. Interestingly, the results comparing the effectiveness of soy isoflaves to metformin in the context of metabolic and inflammatory disorders may also be of interest [136; 137]. In studies by [PERSON] et al. and [PERSON] et al., both soy isoflave and metformin combination therapy was used in the treatment of PCOS [136; 137]. [PERSON] et al. report that body weight was reduced in both groups of rats treated with metformin and soy isoflaves, with a greater reduction in the case of isoflaves, although these differences were not statistically significant. [PERSON] et al. reported that both the group of rats administered with soy isoflaves and metformin showed significantly lower body weight than rats in the PCOS group [137]. The HOMA-IR index and glucose levels were statistically significantly lower in the group of rats with induced PCOS treated with metformin or soy isoflav compared to the PCOS group. After treatment with metformin or genistein, there were slight changes in lipid levels, and statistically significant results were obtained in both groups in terms of LDL cholesterol, which decreased significantly compared to the PCOS group [136]. Both metformin and genistein showed similar results in terms of positive effects on inflammatory markers [136]. In conclusion, the metabolic mechanisms present in PCOS, such as obesity, IR, MASLD, and increased CVD risk, work together and may be important targets for intervention with soy isoflav. To provide an overview of the current state of knowledge regarding the efficacy of soy isoflav in modulating metabolic parameters in women with PCOS, the results of selected clinical studies are summarised below (Table 3).