Stress, Sleep, and Hair Health: How They Influence Hair Loss

Article updated in April 2026

Hair loss is one of the most frequent reasons for consultation at our clinics, both in Madrid and Mexico City. In many cases, patients report noticing an increase in hair shedding during periods of stress, but also following periods of insufficient rest or sleep disturbances.

While the focus has traditionally been placed on stress, in recent years it has been observed that sleep quality and the circadian rhythm may also play a significant role in hair health.

Table of Contents

1. How much hair loss is normal per day?
2. Why does hair fall out?
3. Stress and hair loss: what happens in the body
4. Sleep, the circadian rhythm, and hair loss
5. Does it affect androgenetic alopecia?
6. Frequently asked questions
7. When to seek advice
8. Conclusion

1. How Much Hair Loss Is Normal Per Day?

In a healthy individual, losing up to 100 hairs per day is normal, as part of the natural hair follicle cycle. This hair will be replaced by new growth, maintaining the hair’s natural balance.

The problem arises when this cycle is disrupted and shedding exceeds the body’s capacity for regeneration.

2. Why Does Hair Fall Out?

Alopecia is a multifactorial condition — it is usually caused by a combination of different factors:

• Genetic
• Hormonal
• Nutritional
• Inflammatory
• Environmental

Among the latter, stress and sleep disturbances are playing an increasingly relevant role in clinical practice.

3. Stress and Hair Loss: What Happens in the Body

Stress can affect hair health through several mechanisms:

• Increased cortisol levels
• Greater systemic inflammation
• Disruption of the immune system
• Changes in the hair follicle cycle

As a result, telogen effluvium may develop, in which a greater number of follicles prematurely enter the shedding phase.

In conditions such as alopecia areata, stress can also:

• Promote inflammation
• Disrupt the regulation of the autoimmune response
• Alter hair follicle activity

4. Sleep, the Circadian Rhythm, and Hair Loss

In addition to stress, sleep quality has been identified as a relevant factor in the regulation of the hair cycle.

The hair follicle is influenced by the circadian rhythm — a biological system that regulates multiple bodily functions throughout the day, including growth and regeneration processes.

When sleep is disrupted — whether due to insomnia, insufficient rest, or irregular schedules — this balance may be affected.

From a biological standpoint, these disruptions have been observed to:

• Alter the circadian rhythm of the hair follicle
• Disrupt the expression of genes related to the biological clock, such as the PER3 gene
• Delay the entry into the anagen phase (growth phase)
• Promote prolonged retention in the telogen phase (resting and shedding phase)

Clinically, this may result in increased hair loss or a progressive reduction in hair density, particularly in patients with a pre-existing predisposition.

Furthermore, some conditions associated with sleep disruption — such as obstructive sleep apnoea (OSA) — have been linked to a greater risk of developing androgenetic alopecia.

As with stress, sleep does not usually act as a standalone cause, but rather as a factor that can trigger or worsen pre-existing hair conditions.

5. Does It Affect Androgenetic Alopecia?

Yes, although indirectly.

In androgenetic alopecia (the most common type in both men and women), the following have been observed:

• Reduced expression of the PER3 gene
• Prolonged retention of the follicle in the telogen phase
• Possible acceleration of the miniaturisation process

This suggests that factors such as sleep may influence the progression of this condition, particularly when there is a genetic predisposition.

6. Frequently Asked Questions

Does stress directly cause hair loss?
Not always directly, but it can trigger processes such as telogen effluvium or make pre-existing alopecia more visible.

Is stress-related hair loss permanent?
In most cases, no. When it involves telogen effluvium, it is usually temporary and reversible.

Can poor sleep cause hair loss?
It can contribute to it. Poor sleep quality can disrupt the hair cycle and promote shedding.

Can improving sleep help hair recover?
In some cases, yes — particularly when there is a telogen effluvium component or associated inflammatory factors.

Can this type of hair loss be prevented?
To some extent, yes, through:

• Good sleep hygiene
• Stress management
• Early medical assessment

7. When to Seek Advice

If you notice:

• Greater than usual hair shedding
• Reduced hair density
• Changes in hair thickness or quality

It is advisable to undergo a specialist medical assessment.

An accurate diagnosis makes it possible to identify the cause and propose a personalised treatment plan tailored to each individual case.

8. Conclusion

Stress and sleep disturbances are not the sole cause of hair loss, but they can act as triggering or aggravating factors.

For this reason, when addressing alopecia it is important to consider not only the hair treatment itself, but also the patient’s overall context and general wellbeing.

This content has been prepared by the medical team at the Instituto Médico del Prado and reviewed by Dr. Bonilla Juárez and Dr. Muñoz Ramírez.

If you have noticed changes in your hair or an increase in shedding during periods of stress or sleep disruption, a proper medical assessment can help identify the cause and determine the most appropriate course of action for your situation.

We see patients in both Madrid and Mexico City, tailoring each therapeutic approach to the individual characteristics and evolution of each patient.

The Instituto Médico del Prado is a clinic specialising in the diagnosis and treatment of hair and scalp conditions. If you would like to request an assessment, please contact us through our usual channels.

9. References

1. Boghosian T, Mendez H, Sayegh M, et al. The intersection of sleep and hair loss: a systematic review. Dermatol Ther (Heidelb). 2026.
2. Wu Q, Li M, Xiong Y, et al. Association between sleep patterns, circadian rhythms, and hair loss in young adults. Chronobiol Int. 2025.
3. Peters EMJ, Arck PC, Paus R. Hair growth inhibition by psychoemotional stress. Exp Dermatol.
4. Paus R, Arck P. Neuroendocrine perspectives in alopecia areata. J Invest Dermatol.
5. Gupta MA, Gupta AK. Sleep-wake disorders and dermatology. Clin Dermatol.
6. Trüeb RM. Stress and hair loss: a review. J Eur Acad Dermatol Venereol.
7. Kwon O et al. Human hair growth and stress hormones. Ann Dermatol.
8. Lee S et al. Sleep apnea and androgenetic alopecia. Sleep Med.