The Short Answer: Yes, thyroid imbalance is a leading cause of diffuse hair thinning. The thyroid hormone controls your body's metabolism, which dictates how fast cells reproduce. When you have too little hormone (Hypothyroidism) or too much (Hyperthyroidism), the hair growth cycle is disrupted, causing follicles to shut down and shed prematurely.
How It Affects Your Hair
Hair follicles are some of the fastest-growing cells in the body. Because they require massive amounts of energy, they are often the first thing the body "cuts funding" to when thyroid levels fluctuate.
- Hypothyroidism (Hashimoto's): Causes hair to become dry, brittle, and sparse. You may also lose the outer third of your eyebrows.
- Hyperthyroidism (Graves'): Causes hair to become fine, thin, and shed rapidly due to an accelerated cycle.
Regrowth Strategy: The priority is stabilizing your hormones with medication (like Synthroid) prescribed by your doctor. While you wait for levels to normalize, using Viviscal PRO helps ensure that the follicles have the necessary building blocks to restart the Anagen (growth) phase once the metabolic signal returns.
Common Thyroid Hair Questions
Will the hair grow back?
Yes, thyroid-related hair loss is usually temporary. Once your T3 and T4 levels are stabilized with medication, shedding should stop, though it may take 6 to 9 months for significant volume to return.
Do thyroid medications cause hair loss?
In rare cases, the medication itself (like Levothyroxine) can cause minor shedding during the first month as your body adjusts, but the untreated thyroid condition is almost always the primary cause of the hair loss.