I was six years old when a hospital diagnosed me with thalassemia. I was twenty-five when I found out. The file existed. The diagnosis existed. Nobody told me. That is not an accident of individual incompetence. It is the product of a medical system that was not built to look for answers in a body like mine. Here is what that system has cost — in missed diagnoses, in wrong doses, in avoidable deaths, and in the years between symptom and answer that millions of women are still living through right now.

I have always had a lot of fears. And since a young age I have been adamant about overcoming them. Not tiptoeing around them. Collecting them. Every time I collect one — every time I do the thing and survive it — something happens that still astounds me. How easy the second time is. How there is almost literally no stopping me. I always thought this was a mindset. It is not a mindset. It is fear extinction — and the female brain is specifically, hormonally primed for it at particular points in the cycle. Here is the science behind the thing that has helped me most.

A butterfly-shaped gland the size of a walnut controls your metabolism, heart rate, body temperature, brain, mood, hair, and menstrual cycle. When it goes wrong — and in women it goes wrong 200 times more often than in men — it goes wrong slowly. Quietly. In ways that medicine has spent decades attributing to stress, anxiety, age, and not sleeping enough.

Every heartbeat is a voltage wave. Every pain signal is physics — charged particles crossing a membrane, a signal travelling at the speed of a sprinter. Your body is not just biological. It is electrical. And the physics runs differently in you than the textbooks have ever accounted for.