hair loss with hashis - is thyroid or ferritin the culprit

hair thin, brittle, shedding. TSH is 'normal' per my doc (2.8). pulled my own ferritin: 24. from what i've read ferritin needs to be above 70 for hair growth in women. started iron supplementation + vit C together 3 months ago, ferritin now 55. shed has slowed a lot. if you have thyroid stuff and losing hair, check ferritin. your doc probably won't unless you ask.