A hormone made by fat cells that signals fullness and energy stores to the brain.
Why it matters for PCOS
Leptin is released by fat tissue and tells the brain how much energy the body has stored, helping to regulate fullness and appetite. Leptin levels are usually higher when there is more body fat, and in that state the body can become less responsive to leptin’s signals. In PCOS, leptin is part of a wider appetite and metabolism picture that often overlaps with insulin resistance and weight management.
However, leptin is not a routine PCOS test and rarely changes the treatment plan. Care usually focuses on symptoms and metabolic screening, such as blood sugar, rather than measuring leptin.
This glossary is education, not diagnosis. For your own situation, ask a doctor or pharmacist.