Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in women of reproductive age, which is associated with hormonal imbalances, dyslipidemia, chronic inflammation, and increased oxidative stress, and can increase the risk of cardiovascular and metabolic diseases. Evidence suggests that nutritional interventions play an important role in improving metabolic outcomes in these patients.

This study is a randomized, triple-blind, controlled clinical trial designed to investigate the effect of a light fasting diet combined with magnesium supplementation on lipid profile, lipid peroxidation (malondialdehyde), and C-reactive protein (CRP) levels in women with PCOS. In this study, 46 eligible women were randomly divided into two groups receiving a light fasting diet with magnesium supplementation or placebo, and changes in biochemical and anthropometric indices were evaluated before and after 8 weeks of intervention.

Polycystic ovary syndrome (PCOS) is one of the most common endocrine and metabolic disorders in women of reproductive age, with a significant prevalence worldwide and in the Iranian female population. This syndrome is characterized by a set of hormonal and metabolic abnormalities, including hyperandrogenism, impaired ovulation, dyslipidemia, insulin resistance, mild chronic inflammation, and increased oxidative stress. Evidence suggests that women with Polycystic ovary syndrome (PCOS) have higher levels of inflammatory markers such as C-reactive protein (CRP) and lipid peroxidation indices such as malondialdehyde (MDA), and as a result, are at higher risk for cardiovascular and metabolic diseases. Currently, lifestyle modification including nutritional interventions and physical activity is recommended as the first line of treatment for Polycystic ovary syndrome (PCOS). Meanwhile, intermittent fasting-based diets, especially light fasting, have been proposed as a novel and sustainable approach that can improve lipid metabolism, reduce inflammation, and modulate oxidative stress without severe calorie restriction. On the other hand, magnesium, as an essential micronutrient, plays an important role in regulating glucose and lipid metabolism, increasing insulin sensitivity, reducing inflammation, and inhibiting oxidative processes. However, the evidence regarding the simultaneous effect of light fasting and magnesium supplementation on inflammatory markers and oxidative stress in women with Polycystic ovary syndrome (PCOS) is limited.

The present study is a randomized, triple-blind, controlled clinical trial designed to investigate the effect of light fasting combined with magnesium supplementation on lipid profile, lipid peroxidation, and C-reactive protein (CRP) levels in women with Polycystic ovary syndrome (PCOS). The study population includes women aged 19 to 65 years with Polycystic ovary syndrome (PCOS) with a body mass index equal to or higher than 25 kg/m2, diagnosed by a specialist based on the Rotterdam criteria. After obtaining informed consent, participants will be randomly divided into two groups. The intervention group will receive a light fasting diet with magnesium supplementation (500 mg/day in two doses of 250 mg), while the control group will receive the same light fasting diet with placebo. The nutritional intervention consists of a four-week cyclical program of light fasting designed to gradually adapt the body, and in the second month of the study, a diet with energy intake proportional to daily needs will be implemented to assess the sustainability of metabolic effects.

At the beginning of the study and after the end of the intervention period (8 weeks), anthropometric indicators including weight, Body mass index (BMI), and waist circumference will be measured. Physical activity was also assessed using the standard short-International physical activity questionnaire (IPAQ) and dietary intake was assessed using a three-day 24-hour food recall. Blood samples were collected after 12 to 14 hours of fasting and biochemical markers including total cholesterol, low density lipoprotein (LDL), high density lipoprotein (HDL), triglycerides, malondialdehyde (MDA), C-reactive protein (CRP), and luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured using standard laboratory methods.

Inclusion Criteria:

1. People between the ages of 19 and 65
2. People with a body mass index (BMI) ≤ 25
3. Diagnosis of polycystic ovary syndrome by a specialist based on the Rotterdam criteria

Exclusion Criteria:

1. Failure of the participant to cooperate during the study
2. Use of drug therapy that affects carbohydrate or fat metabolism (including oral contraceptives, insulin sensitizers, antiepileptic drugs, antipsychotics, statins, and fish oil) within the past 6 months.
3. Planning for pregnancy, pregnant, or breastfeeding
4. In the perimenopausal stage
5. Low blood pressure
6. Presence of other diseases (such as congenital adrenal hyperplasia, Cushing's syndrome, androgen-secreting tumors, hyperprolactinemia, diabetes, thyroid disease, severe cardiovascular, gastrointestinal, renal, and hepatic diseases)
7. Performing high-intensity exercise

This is a triple-blind study. Participants, investigators, and outcomes assessors are blinded to group allocation. Only the study coordinator has access to group assignments for safety purposes.