Prediabetes is a metabolic condition associated with increased risk of type 2 diabetes and cardiovascular disease. Intermittent fasting (IF) has emerged as a potential dietary intervention to improve metabolic health, yet comparative evidence among different IF patterns remains limited.

This randomized controlled trial aims to evaluate the effects of three intermittent fasting regimens-5:2 fasting, alternate-day fasting, and time-restricted feeding-compared with a control diet on metabolic parameters, inflammatory markers, body composition, and nutrigenomic profiles in adults with prediabetes.

Inclusion Criteria:

1. Patients with prediabetes, defined according to ADA criteria (fasting plasma glucose 100-125 mg/dL or 2-hour postprandial glucose 140-199 mg/dL).
2. Willing to follow the fasting/diet intervention protocol for 4-6 weeks (depending on the study duration).
3. Signing informed consent and willing to be randomized into one of 3 intervention groups (Monday-Thursday Fasting/5:2, Alternate-Day Fasting/ADF, or Time-Restricted Fasting/IF).

Exclusion Criteria

1. Diagnosis of type 2 diabetes mellitus.
2. Currently undergoing antidiabetic drug therapy (e.g., metformin, sulfonylurea, insulin).
3. Has a severe chronic disease (kidney failure, liver failure, heart failure, or eating disorder).
4. Pregnancy or breastfeeding.
5. History of eating disorders (anorexia nervosa, bulimia nervosa, or binge eating disorder).
6. Taking medications that affect glucose metabolism (e.g., systemic steroids, atypical antipsychotics, etc.). Diagnosis of type 2 diabetes