Polycystic ovary syndrome (PCOS) is one of the most multifactorial disorders and frequent endocrine abnormalities among women in reproductive age [1, 2], which prevalence between 10–15%, depending on diagnostic criteria [3, 4]. Based on the Rotterdam criteria, the prevalence of PCOS in Iran has been reported to be 19.5% [5]. Infertility, endometrial carcinoma, anxiety, impaired hemorrhage, sleep apnea, and metabolic disorders such as obesity, hypertension, type 2 diabetes, impaired gonadotropin secretory activity, insulin resistance, cardiovascular diseases, and metabolic syndrome may be complications of this syndrome [6–10]. Previous studies have indicated that adherence to physical activity and diet treatment recommendations are very important to achieve therapeutic goals [11]. A combination of using medication and lifestyle modifications are treatment plans for this chronic condition [12]. Given that the exact etiology of PCOS is not clear yet, but the interactions between genetic and environmental factors such as diet are considered as effective factors on PCOS [13–16]. Therefore, diet management and weight loss as lifestyle modifications, have been suggested as the primary strategy in the treatment of PCOS [17, 18].
Dietary Approaches to Stop Hypertension (DASH) dietary pattern is a low-glycemic index and low energy-dense diet which has firstly been considered for the regulation of blood pressure [19]. This dietary pattern is rich in vegetables, fruits, whole grains, and low-fat dairy with a reduced content of sodium, saturated and total fat[19]. Therefore, due to these useful ingredients, favorable effects of the DASH diet on insulin resistance, lipid profiles, biomarkers of inflammation and oxidative stress, and PCOS women have also been reported repeatedly [20–23]. Besides, Some studies indicated beneficial effects of the DASH diet on androgens, antioxidant status, body composition, weight loss, AMH (anti-Müllerian hormone), lipid, and metabolic profiles in PCOS women [21, 24, 25]. Also, a randomized controlled trial study conducted by Azadi-Yazdi et al. indicated that adherence to the DASH diet had beneficial effects on androstenedione, SHBG, and antioxidant capacity in women with PCOS [26]. DASH diet contains higher amounts of dietary fiber, phytoestrogens, potassium, calcium, magnesium, folic acid, and other beneficial nutrients [20, 27], which justifies the beneficial effects of this dietary pattern on PCOS. For example, the useful effect of high-fiber and phytoestrogens food on the regulation of testosterone levels in women with PCOS have been mentioned before [28]. As well as, this diet is rich in monounsaturated fatty acids which improve glycemic control and lipid profiles by improves insulin sensitivity [29]. Another related mechanism is the beneficial effect of magnesium on incremental of SHBG level, which correlates with insulin sensitivity and decreases the free fraction of androgens [30]. Therefore, investigating the DASH diet based on other dietary quality indices to clarify other useful features of this healthy diet, will be helpful.
To the best of our knowledge, this study is the first investigation aimed to evaluate the association between adherence to the DASH diet and odds of PCOS in new diagnosed patients in Middle Eastern countries. Also, we adjusted for a wide range of confounding variables including body composition such as body fat percentage in addition to energy intake.