> Quick Answer: Hair loss can be an early indicator of thyroid dysfunction, autoimmune conditions, iron deficiency anemia, hormonal disorders like PCOS, and other systemic health issues. If your hair loss is accompanied by other symptoms—fatigue, weight changes, irregular periods, or skin changes—seek medical evaluation. The hair follicle is a sensitive barometer of overall health.
Your Hair as a Health Indicator
Hair follicles are among the most metabolically active structures in your body. They require steady supplies of nutrients, hormones, and oxygen to function properly. When something is wrong systemically, hair is often one of the first places changes appear.
Research published in Clinical, Cosmetic and Investigational Dermatology found that up to 50% of patients presenting with hair loss had an underlying medical condition contributing to their symptoms1.
Thyroid Disorders: The Most Common Culprit
The Thyroid-Hair Connection
Your thyroid gland produces hormones that regulate metabolism throughout your body—including in your hair follicles. Both too much and too little thyroid hormone can cause hair loss.
Hypothyroidism (Underactive Thyroid)
Affects approximately 5% of women2. Hair-related symptoms include:
- Diffuse hair thinning (not patchy)
- Hair that's dry and coarse
- Loss of outer third of eyebrows (classic sign)
- Slow hair growth
- Hair that breaks easily
Other hypothyroidism symptoms:
- Fatigue and sluggishness
- Weight gain despite normal eating
- Cold intolerance
- Constipation
- Dry skin
- Brain fog
- Depression
Hyperthyroidism (Overactive Thyroid)
Hair-related symptoms:
- Fine, thin hair that won't hold a style
- Diffuse hair loss
- Soft, silky texture (different from normal)
Other hyperthyroidism symptoms:
- Unexplained weight loss
- Rapid heartbeat, palpitations
- Anxiety, nervousness
- Heat intolerance
- Increased sweating
- Tremors
Getting Tested
A simple blood test can evaluate thyroid function:
- TSH (Thyroid Stimulating Hormone): Primary screening test
- Free T4 and Free T3: Actual thyroid hormone levels
- Thyroid antibodies: Can detect autoimmune thyroid disease
If you have hair loss with any thyroid symptoms, request testing.
Iron Deficiency and Anemia
Why Iron Matters for Hair
Iron is essential for:
- Oxygen delivery to hair follicles
- Cell division in the hair bulb
- Enzyme function required for hair growth
Iron deficiency is the most common nutritional deficiency worldwide, affecting up to 30% of women of reproductive age3.
Hair Loss Pattern
Iron-deficiency hair loss typically presents as:
- Diffuse thinning (all over)
- Increased shedding (telogen effluvium)
- Hair that lacks luster
- Slow regrowth
Research in the Journal of Korean Medical Science found that women with hair loss had significantly lower ferritin (iron storage) levels than those without, even when they weren't technically anemic4.
Other Iron Deficiency Symptoms
- Fatigue and weakness
- Pale skin, especially inner eyelids
- Shortness of breath
- Dizziness
- Cold hands and feet
- Brittle nails
- Restless legs
- Unusual cravings (ice, dirt—called pica)
Testing Iron Status
A complete iron panel includes:
- Ferritin: Iron storage (aim for 70+ for optimal hair health)
- Serum iron: Circulating iron
- TIBC: Iron-binding capacity
- Hemoglobin: For anemia diagnosis
Many dermatologists recommend ferritin levels of 70 ng/mL or higher for optimal hair growth—well above the "normal" threshold of 12 ng/mL5.
Autoimmune Conditions
Alopecia Areata
The most direct autoimmune cause of hair loss. The immune system attacks hair follicles, causing:
- Patchy, round bald spots
- "Exclamation point" hairs (short, broken hairs around patches)
- Can affect scalp, eyebrows, eyelashes, or body hair
- Nail changes (pitting, ridges) in some cases
Alopecia areata affects about 2% of the population6. It can:
- Resolve spontaneously
- Recur unpredictably
- Progress to total scalp (alopecia totalis) or body hair loss (alopecia universalis)
Lupus (Systemic Lupus Erythematosus)
An autoimmune disease that can cause:
- Patchy hair loss
- Diffuse thinning
- Hair loss along the hairline ("lupus hair")
- Scarring alopecia (permanent in some cases)
Other lupus symptoms:
- Butterfly-shaped facial rash
- Joint pain
- Fatigue
- Sun sensitivity
- Mouth ulcers
- Kidney problems
Other Autoimmune Conditions
Hair loss can accompany:
- Hashimoto's thyroiditis
- Grave's disease
- Celiac disease
- Psoriasis
- Dermatomyositis
If you have one autoimmune condition, you're at higher risk for others.
Hormonal Imbalances
Polycystic Ovary Syndrome (PCOS)
PCOS affects 5-10% of women and causes:
- Elevated androgens (male hormones)
- Hair thinning on the scalp (androgenetic pattern)
- Excess hair growth on face and body (hirsutism)
- Acne
- Irregular or absent periods
- Weight gain, especially around the midsection
- Insulin resistance
The combination of scalp hair loss with facial/body hair growth is a classic PCOS pattern.
Menopause and Perimenopause
Declining estrogen affects hair:
- Thinner, finer strands
- Slower growth
- More visible scalp
- Changes in texture
These changes can be addressed—explore our hair support options.
Postpartum Hormonal Shift
The dramatic hormone drop after pregnancy causes:
- Significant shedding 2-4 months after delivery
- Can lose up to 30-40% of hair
- Typically resolves by 12 months postpartum
While normal, excessive or prolonged postpartum loss warrants evaluation.
Nutritional Deficiencies
Beyond iron, other deficiencies affect hair:
Vitamin D
- Regulates hair follicle cycling
- Deficiency linked to telogen effluvium and alopecia areata7
- Very common (40% of adults are deficient)
- Get levels tested and supplement if low
Zinc
- Essential for hair tissue growth and repair
- Deficiency causes hair loss and slow regrowth
- Common in vegetarians, those with GI issues, and heavy alcohol users
Biotin (Vitamin B7)
- Severe deficiency causes hair loss
- Rare with normal diet
- Can be depleted by certain medications or GI conditions
Protein
- Hair is 95% protein (keratin)
- Inadequate intake leads to thin, brittle hair
- Common with restrictive diets
Other Systemic Conditions
Diabetes and Blood Sugar Issues
Poorly controlled blood sugar affects circulation and healing:
- Diffuse hair thinning
- Slow hair growth
- Associated with other complications
Kidney Disease
- Can cause diffuse hair loss
- Hair texture changes
- Usually accompanied by other symptoms
Liver Disease
- Hair thinning and loss
- Changes in hair texture
- Usually with other signs (jaundice, fatigue)
Red Flags: When to Seek Medical Evaluation
Seek evaluation promptly if hair loss is accompanied by:
Systemic symptoms:
- Unexplained fatigue
- Unintentional weight changes
- Fever
- Night sweats
Skin changes:
- Rashes anywhere on body
- Scalp redness, scaling, or pain
- Nail changes
Hormonal signs:
- Irregular or absent periods
- Excess facial/body hair
- Acne that started or worsened in adulthood
Other concerning signs:
- Sudden or patchy hair loss
- Hair loss after starting new medication
- Family history of autoimmune disease
- Hair loss with joint pain
Getting Proper Evaluation
What to Expect
A thorough evaluation may include:
Medical history:
- Family history of hair loss and autoimmune conditions
- Menstrual history
- Dietary habits
- Medications and supplements
- Stress levels
- Recent illnesses or surgeries
Physical exam:
- Scalp examination
- Hair pull test
- Examination for signs of systemic disease
- Thyroid palpation
Laboratory tests:
- Complete blood count
- Comprehensive metabolic panel
- Thyroid panel (TSH, Free T4, thyroid antibodies)
- Iron studies (ferritin, serum iron, TIBC)
- Vitamin D level
- Hormone panel if indicated (testosterone, DHEA-S, prolactin)
- ANA if autoimmune suspected
Specialists Who Can Help
- Dermatologist: For hair-specific diagnosis and treatment
- Endocrinologist: For hormonal causes
- Rheumatologist: For autoimmune conditions
- Primary care provider: For initial workup and referrals
Treatment: Addressing the Root Cause
When hair loss signals an underlying condition:
The priority is treating the underlying cause:
- Thyroid medication normalizes hormone levels
- Iron supplementation restores stores
- Autoimmune treatments reduce inflammation
- Hormonal treatments address imbalances
Supporting hair recovery:
While treating the underlying condition, hair-supportive treatments can help:
- Minoxidil stimulates growth and may help while addressing the cause
- Nutritional support ensures follicles have what they need
- Gentle hair care minimizes additional loss
Our hair support formulas combine minoxidil with key nutrients like biotin, vitamin D3, and vitamin K2 to support follicle health while you address underlying causes.
The Bottom Line
Hair loss isn't just a cosmetic concern—it can be your body's way of signaling that something needs attention. If your hair loss is accompanied by other symptoms, don't dismiss it. A proper medical evaluation can identify treatable conditions early, when intervention is most effective.
Your hair deserves attention. So does the rest of your health.
Explore hair support options | Contact our care team
References:
This article is for informational purposes only and does not constitute medical advice. Consult with a healthcare provider for diagnosis and treatment of any health condition. Compounded medications are not FDA-approved finished drug products.