Hair Loss (Alopecia)
What causes hair loss?
Hair loss, or alopecia, can be caused by a variety of factors including heredity, hormones, some medical conditions and aging. The specific cause may vary from person to person. Here are some common causes of hair loss:
Androgenetic Alopecia
This is the most common cause of hair loss and is often referred to as male or female pattern baldness. It is hereditary and primarily influenced by genetics and hormonal factors. This means
that your inherited genes cause hair follicles to shrink and eventually stop growing hair. It affects up to 50% of men and women. In men, it typically results in a receding hairline and balding at the crown, while in women, it leads to diffuse thinning of the hair.
Pattern hair loss is genetically predetermined, caused by male hormones called androgens, particularly DHT. Testosterone is metabolized by the hair follicles shortening the growth phase of the hair cycle. This leads to miniaturization of the hair follicles, which slows and eventually stops hair growth. The goal of treatment is to block the effects of testosterone.
Treatments can help to slow or stop hair loss and help regrow hair so long as the hair follicles are still alive. Once the follicle dies it cannot be revived. That is why getting the correct diagnosis and treatment at the first sign of hair loss, usually at the temples in men, is so important.
Telogen Effluvium
Telogen Effluvium is a non-scarring alopecia characterized by acute hair sheading. This type of hair loss is often triggered by a significant stressor or change in the body, such as surgery, childbirth, illness, or severe trauma or emotional stress, and from postpartum and menopausal hormonal changes, hypothyroidism, decreased estrogen, crash dieting, low protein intake, heavy metal ingestion and iron deficiency and some medications like beta-blockers, retinoids, anticoagulants, and more. It can occur to people at any age, any gender and any racial background. However, women are more likely to experience telogen effluvium due to hormonal changes.
A careful history and physical examination are needed to diagnose the cause. Laboratory testing may be needed to determine if there is a metabolic, nutrient deficiency or hormonal cause. Acute telogen effluvium is a self-limited condition. If the cause can be identified by history, no treatment is necessary. However, if a hormonal or dietary imbalance or other factors are involved, they must be identified and treated after which hair growth will restart.
Alopecia Areata
Alopecia areata is an autoimmune disorder in which the immune system mistakenly attacks hair follicles, causing hair loss in small, round patches. It can affect both the scalp and other areas of the body. Many therapies are available to treat alopecia areata including topical, systemic and injectable options.
It appears to have a genetic basis. Incidence increases with age. Mean onset age is between 25 and 36. Onset is fast and may progress to complete hair loss on the scalp and can also cause hair loss on the entire body. However, frequently there is spontaneous remission so leaving it untreated is an option for many patients. Topical corticosteroids are typically the first-line treatment for most patients.
Medications and Treatments
Certain medications and medical treatments, such as chemotherapy, radiation therapy, and some blood pressure medications, can cause hair loss as a side effect.
Hormonal Changes
Hormonal changes due to conditions like pregnancy, menopause, thyroid disorders, or polycystic ovary syndrome (PCOS) can lead to hair loss.
Nutritional Deficiencies
Inadequate intake of essential nutrients like iron, vitamin D, and protein can contribute to hair loss.
Scalp Conditions
Conditions like dandruff, psoriasis, or fungal infections of the scalp can lead to hair loss if left untreated.
Traction Alopecia
Excessive pulling or tension on the hair, often due to tight hairstyles like braids, cornrows, or ponytails, can cause hair loss over time. Stopping the tension allows the hair to regrow.
Trichotillomania
This is a psychological disorder characterized by the compulsive urge to pull out one’s own hair, which can lead to hair loss.
Age
Hair naturally thins as a person ages, and some degree of hair loss is a normal part of the aging process.
Your Coastal Skin and Eye board-certified dermatologist will review your medical history, listen to your concerns and inquire about you symptoms and potential causes. They will conduct a physical examination and may perform other tests to reach a diagnosis.
If you notice your hair is falling out, it is important to contact Coastal Skin and Eye Institute to schedule a consultation at our office in Encinitas or Carmel Valley to receive the correct diagnosis. Early intervention is often more effective in addressing hair loss. Once the underlying cause is determined, appropriate treatment options can be considered.
References
- Lepe K, Zito PM. Alopecia Areata. [Updated 2023 Aug 14]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537000/
- Ho CH, Sood T, Zito PM. Androgenetic Alopecia. [Updated 2022 Oct 16]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK430924/
- Hughes EC, Saleh D. Telogen Effluvium. [Updated 2023 May 29]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK430848/
