wellness-guides

PCOS Diet Plan for Irregular Periods: What the Evidence

A PCOS diet plan focused on improving cycle regularity — what to eat, what to avoid, and which supplements have real RCT evidence for PCOS and periods.

PCOS is not one condition. The term covers several different hormonal patterns — insulin resistant PCOS, adrenal PCOS (driven by DHEA S excess), inflammatory PCOS, and post pill PCOS (where suppressed ovulation re emerges irregularly after stopping hormonal contraceptives). The dietary approach that works best depends on which pattern you have. That said, insulin resistance is present in the majority of PCOS cases, and the dietary evidence for improving it is the strongest in the PCOS literature. This guide focuses primarily on the insulin resistance mechanism while noting where the evidence applies more broadly. The Core Mechanism: Insulin and Androgens In insulin resistant PCOS, the sequence works like this: 1. Insulin resistance → elevated fasting insulin 2. Elevated insulin → ovarian theca cell stimulation → excess androgen (testosterone, androstenedione, DHEA) production 3. Elevated androgens → arrest of follicle development (the follicles start growing but stop before the LH surge can occur, creating the characteristic "string of pearls" on ultrasound) 4. No LH surge → no ovulation → no corpus luteum → no progesterone → irregular or absent periods Reducing insulin resistance