08/30/2026
That viral nail moon video hit 6 million views telling women their missing lunulae mean low thyroid energy. It's not true. Nail changes have no validated diagnostic link to thyroid function. But the reason it spread is real. So many women get only a TSH test, which can sit normal for years while Free T3 is too low to reach the brain or the cells. Here are the labs to ask for by name at your next appointment. Free T3 with a functional target of 3.2 to 4.2 pg per mL, Free T4, Reverse T3 and TPO antibodies. Bring this list with you.