Effect of NMN (Nicotinamide Mononucleotide) on Polycystic Ovary Syndrome

Inclusion Criteria: 1. Individuals who are 20 to 40 years old; 2. BMI \< 25 kg/m2; 3. Individuals with PCOS should meet all the Rotterdam diagnostic criteria: 1) Oligo- and/or anovulation; 2) Clinical and/or biochemical signs of hyperandrogenism; 3) Polycystic ovaries, and exclusion of other aetiologies (congenital adrenal hyperplasia, androgen-secreting tumors, Cushing's syndrome). 4. Individuals who can insist on continuous monitoring in the outpatient clinic. 5. Individuals who are not participating in other research projects currently or 3 months before the intervention. Exclusion Criteria: 1. Individuals who suffering from other diseases that may cause hyperandrogenism and ovulation abnormalities. 2. Individuals who are during pregnant, lactation or menopause. 3. Individuals who currently receiving weight-loss drugs or surgery or within the past 2 months. 4. Individuals who take niacin, nicotinamide, or other vitamin B-related supplementation currently or within the past 2 months. 5. Individuals who need regular medication to treat chronic diseases such as diabetes, hypertension, gout, hyperuricemia, etc. 6. Use of medications that affect hormone levels, appetite, carbohydrate absorption, and metabolism within the past 2 months. 7. Individuals with severe liver diseases or kidney disease that are ineligible to participate in the study. 8. A medical history of severe cardiovascular and cerebrovascular diseases. 9. Individuals who currently suffer from severe gastrointestinal diseases or undergo gastrointestinal resection that may affect nutrient absorption. 10. Individuals who drink more than 15g of alcohol per day or have a smoking habit. 11. Individuals who need drug treatment for any mental illness such as epilepsy and depression. 12. Cancer patients. 13. Individuals who suffer from infectious diseases such as hepatitis B, active tuberculosis, AIDS, etc.