More than 80 million Americans are experiencing some form of hair loss right now. The truth is that hair loss is often a visible signal of something happening deeper inside your body — and in many cases, identifying and treating the root cause can slow, stop, or even reverse the process.
By Dr. Kathryn Kline, MD · Board-Certified Family Medicine Physician · Published 2026-04-08
More than 80 million Americans are experiencing some form of hair loss right now — roughly 50 million men and 30 million women — making it one of the single most common reasons patients bring concerns to their primary care doctor. In Texas alone, hair loss is the most frequently searched health symptom online, outpacing even headaches and back pain. Yet despite how common it is, hair loss remains one of the most misunderstood conditions in medicine. Most people assume it's purely genetic and untreatable, or they spend months cycling through over-the-counter shampoos and supplements before ever asking a physician what's actually going on. The truth is that hair loss is often a visible signal of something happening deeper inside your body — and in many cases, identifying and treating the root cause can slow, stop, or even reverse the process.
Every hair on your head cycles through three phases: anagen (active growth, lasting 2–7 years), catagen (a brief transitional phase), and telogen (a resting phase lasting about 3 months, after which the hair sheds naturally). At any given time, roughly 85–90% of your hair is in the growth phase and 10–15% is in the resting phase. Losing 50 to 100 hairs per day is completely normal.
Hair loss becomes a medical concern when something disrupts this cycle — either by pushing too many hairs into the resting phase at once, by shrinking the hair follicles themselves, or by triggering inflammation that damages follicles permanently. Understanding which mechanism is at work is the key to effective treatment, and it's why a proper medical evaluation matters far more than anything you'll find in the supplement aisle.
Yes. Significant physical or emotional stress can trigger telogen effluvium, causing a large number of hairs to shift into the resting phase simultaneously. The shedding typically appears 2–3 months after the stressful event and is usually temporary, resolving within 6–12 months once the stressor is managed.
Biotin (vitamin B7) is one of the most marketed hair supplements, but clinical evidence only supports its use in patients with a documented biotin deficiency — which is rare. For most people, taking high-dose biotin does not improve hair growth. It can, however, interfere with certain lab tests (including thyroid panels), so it's important to disclose supplement use to your doctor.
Most hair loss treatments require 3–6 months of consistent use before visible improvement, with full results often taking 9–12 months. This is because hair follicles need to re-enter and progress through the growth (anagen) phase. Patience and consistency are essential — stopping treatment prematurely is the most common reason patients don't see results.
Yes. A telehealth visit is well-suited for the initial evaluation of hair loss. Your physician can take a detailed history, identify potential triggers, and order the appropriate lab work — all via video. In most cases, the diagnosis and treatment plan can be established without an in-person visit. If a scalp biopsy or in-person dermatologic exam is needed, your physician will refer you accordingly.
While standard lab reference ranges may list ferritin as 'normal' at levels as low as 12–15 ng/mL, many dermatologists and hair loss specialists recommend maintaining ferritin levels above 40–70 ng/mL for optimal hair growth. If your level is in the low-normal range and you're experiencing hair loss, iron supplementation may help — but should be guided by your physician.
In most cases, yes. Medication-induced hair loss (telogen effluvium) is typically reversible once the offending medication is discontinued or changed. However, you should never stop a prescribed medication without consulting your doctor first — there may be alternative medications that don't affect hair growth.