This study was planned to examine the prevalence of vitamin D insufficiency, insulin resistance, non-alcoholic fatty liver disease (NAFLD), and their relationship with each other and the nutritional status of individuals with polycystic ovary syndrome (PCOS) in reproductive age, by evaluating anthropometric, biochemical, and ultrasonographic findings and food consumption frequency data.

A total of 72 female individuals diagnosed with PCOS were included in the study. Nutritional status, physical activity levels, anthropometric measurements, and biochemical parameters of individuals were examined. A food consumption frequency questionnaire was applied to the individuals. According to the 2003 Rotterdam Consensus revision, PCOS is diagnosed when at least two of the following three conditions are present: Polycystic ovaries on ultrasonography, oligomenorrhoea, or anovulation; clinical and/or biochemical symptoms of hyperandrogenemia. Testing was done on insulin, lipid profiles, fasting plasma glucose, and liver function. Bioelectrical impedance analysis was used to determine body weight and composition. An abdominal ultrasound was used to diagnose NAFLD.

Inclusion Criteria:

• female sex
• PCOS diagnosis
• no use of oral contraceptives or any hormone therapy in the last 3 months
• no use of vitamin D supplements in the last 3 months
• no use of oral antidiabetic drugs in the last 3 months

Exclusion Criteria:

• adrenal dysfunction
• diabetes mellitus
• pregnancy
• alcohol consumption
• a history of chronic viral hepatitis
• autoimmune liver disease
• other liver diseases
• history of hepatotoxicity
• use of antihypertensive, antidiabetic, lipid-lowering drugs

The appropriate sample size was determined to be 65 using power analysis in accordance with the results of the prior studies, with a 90% confidence interval and a 0.05 type-I error. The Rotterdam Consensus, revised in 2003, defined polycystic ovary syndrome (PCOS) as the presence of at least two of the following three criteria: (i) oligomenorrhoea or anovulation; (ii) clinical and/or biochemical signs of hyperandrogenemia; and (iii) ultrasound-confirmed polycystic ovaries. 328 volunteer women who visited the clinic throughout the research period were chosen as participants after being screened for eligibility. This study included 72 women who were confirmed to be eligible and ranged in age from 18 to 40.

The data are not publicly available due to ethical concerns.