The goal of this clinical trial is to investigate the effects of a specific dietary program on overweight or obese patients with polycystic ovary syndrome (PCOS) through a multicenter, randomized, controlled, prospective study design.

The main questions it aims to answer are:

1. Does the specific dietary program increase the clinical remission rate of PCOS in overweight or obese patients?
2. Does the specific dietary program improve metabolic and anthropometric outcomes in overweight or obese patients with PCOS compared with conventional intervention?

Researchers will compare the effects of a specific dietary program versus conventional intervention on clinical remission rates, metabolic outcomes, and anthropometric measures in overweight or obese patients with PCOS.

Participants will:

1. Receive either a specific dietary intervention or conventional intervention for 24 weeks.
2. Undergo assessments every 12 weeks throughout the study period.

Inclusion Criteria:

1. Female participants aged 18-49 years.
2. Body mass index (BMI) ≥ 24 kg/m² and waist circumference ≥ 85 cm.
3. Diagnosis of polycystic ovary syndrome (PCOS) based on the 2003 Rotterdam consensus, defined by the presence of at least two of the following three criteria: (i) Oligo-ovulation and/or anovulation; (ii) Clinical and/or biochemical signs of hyperandrogenism; (iii) Polycystic ovarian morphology on ultrasonography, defined as the presence of ≥12 follicles measuring 2-9 mm in diameter in each ovary and/or increased ovarian volume ≥10 cm³.
4. Menstrual irregularity.
5. Use of reliable non-hormonal contraception throughout the study period.
6. Provision of written informed consent.

Exclusion Criteria:

1. Participants with non-classical 21-hydroxylase deficiency, hyperprolactinemia, Cushing's disease, or adrenal tumors will be excluded from the study.
2. Participants who are postmenopausal or perimenopausal, as well as those who are pregnant, planning pregnancy, or currently lactating, will be excluded.
3. Participants with a history of substance abuse, acute infectious diseases, or diabetes mellitus will not be eligible for inclusion.
4. Participants with a history of malignancy within the past 5 years or with current malignant disease will be excluded.
5. Participants with a history of gallstones or gout will be excluded from the study.
6. Participants with poorly controlled thyroid disorders, regardless of etiology, will be excluded.
7. Participants who have been diagnosed with an eating disorder within the past 12 months will be excluded.
8. Participants with known intolerance or allergy to components of the study dietary plan, such as soy, lactose, or gluten, or those diagnosed with celiac disease, will be excluded.
9. Participants who have used medications that may affect reproductive or metabolic outcomes within the past 3 months will be excluded, including oral hormonal contraceptives or hormonal implants; anti-androgens (e.g., spironolactone, flutamide, finasteride); metformin or other insulin-sensitizing agents; clomiphene citrate or estrogen modulators; gonadotropin-releasing hormone (GnRH) modulators (e.g., leuprolide); minoxidil; weight-loss medications; or other drugs that may influence appetite, such as oral corticosteroids.
10. Participants with severe hepatic impairment, defined as alanine aminotransferase (ALT) > 100 U/L or aspartate aminotransferase (AST) > 100 U/L, will be excluded.
11. Participants with severe renal impairment, defined as an estimated glomerular filtration rate (eGFR) < 80 mL/min, will be excluded.
12. Participants with severe cardiovascular or cerebrovascular disease, including unstable angina, heart failure classified as New York Heart Association (NYHA) class III or higher, or those in the acute phase of cerebral infarction, will be excluded.
13. Participants who are currently participating in another clinical trial will be excluded.
14. Participants with any other medical condition or circumstance that, in the opinion of the investigators, makes them unsuitable for participation will be excluded.

IPD will not be shared due to privacy concerns and the need to protect sensitive participant information. Sharing the data could potentially breach confidentiality agreements and ethical guidelines, as the de-identified data might still be traceable back to participants. Additionally, the research team has not obtained prior consent for data sharing, and sharing IPD would require additional approvals from the ethics committee and participants.