Updated: May 18
Hair loss can be very distressing, having significant impact on an individual's quality of life. Some report early and others sort of move into a state of denial and don't share their concerns with their practitioner until significant hair loss has occurred, whether patchy or diffuse. Sometimes too, hair loss may be related to an incessant need to pull one's own hair, whether on the scalp or even the eyebrows and eyelashes.
Not an uncommon finding in family practice, but the underlying cause can be a plethora of issues, that yes, goes beyond #thyroid health, even beyond genetics and hormones. Either way, it is a symptom and when you understand the symptom, you can potentially rectify the underlying problem. It's important though to address this early, because the more your hair sheds, the thinner those hair follicles become, which can lead to scarring which is not reversible.
The patterns of hair loss offers a great deal of information to the underlying cause, as patchy bald spots are more often related to alopecia areata, which Jada Pinkett Smith has now become infamous for, a bit more of a subtle presentation of hair loss. When more diffuse, this may be related to telogen effluvium. Nutrient deficiencies maybe be the cause, as could gut dysbiosis, hormonal imbalances, COVID shedding, anemia, poor digestion, malabsorption, chronic inflammation, adrenal fatigue, food sensitivities, poor circulation, systemic lupus erythematosus, syphilis, infection, toxins or molds, chronic viruses or illnesses, depression, major stress and trauma, antigliadin antibodies, various skin diseases, genetics, high fever, crash or liquid diets, fungal imbalances, parasites, mass cell activation, and heavy exercise.
No matter the cause, the clinician first starts with a detailed history and physical exam. We first want to know if this hair loss is scarring or not (noncicatricial), which suggests whether it is reversible or permanent. Scarring #alopecia (cicatricial) is rare with a plethora of potential underlying causes. Often this is related to an underlying autoimmune disease such as Lupus. If follicular orifices are absent, the alopecia is more likely scarring and these clients, we refer to dermatology. When hair loss appears to be nonscarring though, typically clients remain with their primary care practitioner and here's what we identify and how we may approach treatment.
First know that hair grows in three phases, which is helpful in understanding how long you might be dealing with any particular stage. Pregnant women for example, have such as high volume of blood that their hair is more readily nourished and can grow quite thick and long during pregnancy, as do their nails. After they birth however, this blood volume returns to normal and that hair can start to fall out determining on its stage of growth. This can be normal, but it can also be a sign of postpartum thyroiditis, so knowing these stages is helpful.
The anagen stage is when our hair is actively growing and 90 percent are in this phase at any given time. The catagen phase is then the degenerative stage, which fewer than 10 percent are in at any point, and the telogen phase is when our hair is at rest, as well as when it sheds, which comprises about 5 to 10 percent of our body and scalp hair. Postpartum women shed that overgrowth hair then in the telogen phase.
When evaluating hair loss, we evaluate first, its presentation. Patchy hair loss for example, is often due to alopecia areata, tinea capitis, and trichotillomania. When the loss is more diffuse, this is commonly due to telogen or anagen effluvium. Androgenetic alopecia may be more diffuse, or it may be in a more specific pattern, and it may progress towards complete baldness.
Hair that comes out in clumps suggests telogen effluvium. If there are systemic symptoms, such as #fatigue and weight gain, then we think thyroid disease. Febrile illness though, or stressful events, even recent pregnancy can account for diffuse hair loss of telogen effluvium. Hair products too, particularly hair straightening agents or certain shampoos, suggests a diagnosis of trichorrhexis nodosa.
What does all this Latin mean? Alopecia areata is the hair loss that happens pretty quickly and in a more patchy manner. We will see short, thin or vellus hairs (peach fuzz), yellow or black dots, and broken hair shafts. This typically grows back without interventions, but sometimes injections are helpful.
Hair loss that happens days to weeks after exposure to a chemotherapetuic agents is called anagen effluvium. This happens about 65 percent of the time after chemotherapy for example. No medications have proven helpful, although minoxidil may be helpful during the regrowth stage. Tea tree oil shampoo is often an overlooked underlying cause of hair breakage.
When hair loss is consistent in the family, and progressively gets worse, especially in men, it is often related to androgens or male hormones. This does happen to some women as well, as they age. Men will notice this on the sides of their heads, as well as the front and crown. They may experience complete hair loss with some hair on the fringes remaining. Women often have more diffuse hair thinning sparing the frontal hairline. Minoxidil can be applied topically for both men and women, although not as strong for women typically. This treatment does have to continue indefinitely because hair loss reoccurs when treatment is discontinued. This treatment may be irritating to some however.
Telogen effluvium is diagnosed when individuals share of hair loss happening in clumps, particularly in the shower or hairbrush. This may be a physiologic issue or may even be related to emotional distress. We have to discern the underlying cause and address that, but more often this is self-limiting and resolves in two to six months.
Tinea capitis is common. This one also presents patchy and is related to an infection in the hair shaft and follicles. This one does need treatment with an antifungal, but treatment typically is oral because antifungals do not penetrate the hair follicles typically. A few different species can be presenting here, so depending on the offender, treatment may differ somewhat. Lamisil, Sporanox, and Diflucan are common.
Trichorrhexis nodosa is yet another diagnosis, and this is related to breakage secondary to trauma, so like carrying your purse on your shoulder, excessive brushing, applying heat or hairstyles that pull on hair. The fix here is to stop the offending actions, although labs should evaluate overall health, iron levels, copper, liver-functioning and the thyroid. On examination, hairs appear to have white nodes, but on closer inspection you can see that these are the fracture sites along the shaft and the cortex has split into several strands.
A few years ago, my hair was breaking off, super thin from the neck down and after a process of elimination, realized that I was borrowing my partner's tea tree oil shampoo which was drying my hair and making it break. Exposures such as bleach in the hair and even excessive exposure to salt water can be damaging to the hair. There are also a few congenital or genetic conditions that may cause trichorrhexis nodosa, including trichorrhexis invaginata (bamboo hair), intussusception of the hair shaft at the keratinization zone, Menkes disease, keratinization defects due to defective copper metabolism, and argininosuccinic aciduria. Rarely this can be a manifestation of hypothyroidism.
Another more common cause of hair damage and loss is trichotillomania, where patches of alopecia are apparent, typically in the front or side of the head, maybe progressing backwards, or as mentioned previously, may include the eyelashes and eyebrows. I've also seen this with men's chesthair and also arm hair. This one doesn't really have a perfect solution, although SSRIs (anti-depressants) may be helpful. Behavioral therapy can help, and both together is probably best. I often see this as part of my ADHD diagnosis and when treatment is initiated, most often naturally in my practice, this does resolve.
Sometimes this is related to iron deficiency or even a nutritional disorder, so we not only evaluate the individual physically, but ask questions to help us better identify the cause. Labs and even stool testing or nutrient and metabolic testing can be helpful, as well as food and genetic testing. We want to consider more underlying issues like thyroid disease, and can rule these in or out through obtaining laboratory testing. Fungal cultures may prove helpful or even the client sharing a history of pulling at their hair. There isn't really a recommendation for routine tests though, as there are so many potential causes and history can really direct us well.
If you are experiencing hair loss and want help identifying the underlying cause and to discuss treatment options, connect with Dr. Layne. We can also offer advice on supporting healthy hair growth. Your hair and nails are a reflection of your overall health, so if these aren't optimal, they may be signs of underlying concern.
Phillips, T. G., Slomiany, W. P., & Allison, R. (2017). Hair loss: Common causes and treatments. American Family Physician, 96(6), 371-378.