Why Stress Causes Thinning Hair — And What We Can Do About It

At Sheen Vein (Aesthetics & Functional Medicine), one of the most common concerns we hear from patients in Clayton, Chesterfield, Arnold, Farmington, and the greater St. Louis area is this:

"Why is my hair suddenly getting thinner?"

And more often than not — stress is a major part of the story.

Hair thinning is rarely just cosmetic. It is often a signal from the body that something deeper is happening metabolically, hormonally, or neurologically. Chronic stress disrupts multiple pathways that regulate the hair growth cycle.

Let’s walk through this together in a way that makes sense.

Understanding the Hair Growth Cycle

4

Hair grows in three phases:

1. Anagen (growth phase)
2. Catagen (transition phase)
3. Telogen (resting/shedding phase)

Under healthy conditions, about 85–90% of hair is in the growth phase.

When the body experiences significant stress — emotional trauma, illness, surgery, hormonal disruption — large numbers of hair follicles prematurely shift into the resting (telogen) phase. This condition is called telogen effluvium.

Patients often notice:

• Sudden shedding in the shower
• Thinner ponytail
• Hair all over the brush
• Increased scalp visibility

The shedding usually occurs 2–3 months after the stress event, which is why many people don’t connect the dots.

Cortisol: The Primary Culprit

When we are stressed, our adrenal glands release cortisol. In small bursts, cortisol is protective. But chronic elevation changes physiology:

• Constricts blood flow to peripheral tissues (including hair follicles)
• Increases inflammation
• Disrupts thyroid function
• Alters sex hormones
• Increases insulin resistance

Hair follicles are metabolically active. They require oxygen, nutrients, and hormonal balance. Cortisol compromises all three.

Stress, Insulin, and Hair Loss

Many patients don’t realize that stress also elevates blood sugar and insulin.

When insulin remains chronically elevated:

• Androgens increase
• DHT (dihydrotestosterone) increases
• Scalp inflammation worsens

In women especially, stress-induced insulin resistance can trigger or worsen androgen-related hair thinning.

We frequently evaluate this through comprehensive metabolic testing in our Functional Medicine services at Sheen Vein
👉 https://sheenvein.com

Stress and Thyroid Suppression

Chronic cortisol suppresses thyroid conversion (T4 → T3).

Low or suboptimal thyroid function slows hair growth dramatically. Many patients in the St. Louis area are told their labs are “normal,” yet they continue losing hair.

Functional ranges matter.

We look deeper at:

• Free T3
• Reverse T3
• Thyroid antibodies
• Ferritin levels

Hair follicles are extremely sensitive to low ferritin and thyroid dysfunction.

The Inflammatory Connection

4

Stress activates inflammatory cytokines such as:

• IL-6
• TNF-alpha
• CRP

Inflammation damages the microenvironment around the follicle. Over time, follicles miniaturize.

This is why addressing stress isn’t just “mental health.” It is anti-inflammatory medicine.

What We Do at Sheen Vein

In Clayton, Chesterfield, Arnold, and Farmington, our approach is comprehensive:

1. Root Cause Evaluation

• Cortisol rhythm testing
• Insulin and HOMA-IR
• Thyroid panel
• Ferritin
• Hormone assessment

2. Nutrient Optimization

Hair requires:

• Iron (optimal ferritin above 70)
• Zinc
• Vitamin D
• B vitamins
• Protein

3. Hormone Balance

Perimenopausal and menopausal women often experience hair thinning due to estrogen decline and relative androgen dominance.

Our hormone optimization services:
👉 https://sheenvein.com/functional-medicine

4. Regenerative Hair Therapies

We also offer regenerative scalp therapies to stimulate follicles and improve circulation.

👉 https://sheenvein.com/aesthetics

Stress Reduction is Medical Treatment

We recommend:

• Resistance training
• Morning sunlight
• Blood sugar stabilization
• Sleep optimization
• Nervous system regulation

Hair regrowth takes time. Follicles require 3–6 months to recover once stress pathways normalize.

When to Seek Help

If you notice:

• Shedding lasting more than 3 months
• Scalp discomfort or itching
• Widening part
• Hair thinning with fatigue

It’s time for a deeper evaluation.

Final Thoughts

Hair thinning is often the body’s whisper before it becomes a shout.

Stress changes cortisol.
Cortisol changes insulin.
Insulin changes hormones.
Hormones change follicles.

If you’re in St. Louis, Clayton, Chesterfield, Arnold, or Farmington, we’re here to help you look beyond surface symptoms and restore balance.

Schedule a consultation:
👉 https://sheenvein.com

‍