Sudden rapid hair loss. I've experienced it myself. Twice, in fact.
The first time, I was traveling overseas for the summer. On my first night, after a wonderful dinner of lamb, I came down with food poisoning. From that point on, for the next 2 months, I stayed away from all meat. In fact, I watched every food choice extremely carefully.
It worked. I didn't get sick again. I also lost 15 pounds over the span of 2 months.
Then I came back to Houston and slowly gained the weight back. But about 3 months later, I started to lose something else. My hair.
Over the next few months, I started losing noticeable amounts of hair. I would run my hands over my head, and I would pull out strand after strand of hair. By the roots, no less. In the shower, I would see many strands of hair in the drain, and my hairbrush would be full of hair after just a gentle brushing.
I had developed telogen effluvium.
Telogen effluvium: when your hair follicles go into hibernation
As a dermatologist, I've treated many patients with this condition over the years.
Why does it occur?
Telogen effluvium (TE) essentially happens when your hair follicles go into a state of hibernation. Your hair follicles aren't always actively growing. In fact, your hair follicles naturally cycle through 3 main phases:
An actively growing phase (anagen)
A destructive phase (catagen)
A resting phase (telogen)
(We'll come back to this point, but just remember: during the resting phase (telogen), it's very easy to pull hairs out by the root.)
In normal times, most of our hair follicles are actively growing, and are strongly anchored into our scalp. In fact, approximately 85% of our hair follicles are actively growing under normal conditions.
Sometimes, though, events can occur that send a signal. This is what happens in TE: an event will suddenly trigger most of our hair follicles to enter a state of hibernation.
That's why so many of my patients tell me that just gently brushing their hair will lead to hair loss. It's because those hairs are in a resting phase. As the growing hairs deep in the follicle start to push the resting hairs up and out of the hair follicle, any gentle pressure on the hair will tug them out.
Triggers for telogen effluvium: when pregnancy, surgery, hospitalization, or sudden weight loss puts severe stress on your body's systems
There are different events that can act as triggers for TE. These triggers have one thing in common: they cause a severe physical stress to the body.
One of the most common triggers is pregnancy, because of the high amount of physical stress that it puts on the body. Other triggers include illnesses (such as high fevers), or surgeries, or prolonged hospitalizations. Sudden weight loss can do it, as can a low-protein diet. While severe emotional stress is a less common trigger, it has also been described as a trigger.
The most important question: will I lose all my hair?
With TE, the first question I'm usually asked is "Why? Why did this happen to me?"
That's usually followed by "Am I going to lose all of my hair?"
The good news is that in most cases of TE, the hair will return to its original fullness.
That's what happened to me. The hair loss continued for about 4 months or so. And then I started to see the hair loss slowing down. I was seeing fewer and fewer strands of hair in my hairbrush. At this point, I had lost serious fullness in my hair. But over the next 6 months, my hair started to slowly regain its former fullness.
And then eventually it was back.
That's very typical. For most people, the severe physical stress occurs, and then about 3 months later the hair loss begins. That hair loss will then continue for another 3 to 6 months, sometimes even longer, and then the hair loss will start to slow down. Then, finally, you'll notice the hair slowly starting to regrow. While the hair loss may be sudden, the process of regrowth is a slow one. But eventually, most people will experience full, or close to full, hair regrowth. And even during TE, most patients do NOT lose all of their hair. Instead, they experience all-over thinning of their hair.
TE is NOT likely to cause patchy hair loss, or redness or pustules in the scalp, or scarring of the skin of the scalp. These findings point to another diagnosis, and would warrant further testing.
What to do if you're experiencing TE
When somebody describes the "hairbrush sign" to me, I think of TE. Specifically, if they describe that their hair is falling out by the roots, or they tell me that they're seeing many hair strands in their hairbrush or the shower drain, I'll suspect TE.
I'll then start asking questions. I'm specifically looking for triggers for that severe physical stress to the body.
If it's pregnancy, or a hospitalization, or surgery, then the TE will likely just turn around on its own.
Will topical minoxidil (brand name Rogaine) help? Rogaine is an over-the-counter treatment that helps to slow down hair loss due to male pattern hair loss or female pattern hair loss. It's not known whether the use of minoxidil solution or foam will help in TE, but if we believe that the patient is also experiencing male or female pattern hair loss, then dermatologists will sometimes recommend its use. (Check with your dermatologist.)
If a patient tells me that they've made a dramatic change in their diet, then I will delve further. Are they consuming enough protein? If they're vegetarian or vegan, or following another type of restrictive diet, are they getting enough iron and zinc? Those 2 nutrients in particular have been linked to hair loss. If there's any question, I'll recommend testing and a consultation with a nutritionist.
If you'd like to read more, this is my handout on the dermatologist's approach to hair loss, and this is our article in a medical journal on the links between diet and hair loss.