She went to three different doctors. All three said the same thing: "Your labs are normal. It's probably stress. Maybe depression." But she knew something was wrong. The fatigue was bone-deep. The hair clogging the shower drain. The 15 pounds that appeared overnight and refused to leave regardless of what she ate. She wasn't imagining it. She had subclinical hypothyroidism — a condition affecting over 20 million women that falls below the radar of standard thyroid panels.