There are two types of hair loss that concern men most: hereditary baldness and the sudden, diffuse hair loss that sometimes seems to come out of nowhere. That second type often has a name you probably don't know: telogen effluvium.
If you've been losing more hair than usual in recent months when showering, on your pillow, or in your brush, but you don't have a clear pattern of a receding hairline or thinning crown, chances are stress is the cause. And that's fundamentally different from genetic hair loss.
In this article, I explain what telogen effluvium is, how to recognize it, how long it lasts, and what you can do about it.
What is telogen effluvium?
Your hair grows in cycles. Most hairs are in the growth phase (anagen), a smaller group in the transitional phase (catagen), and about 10-15% rest in the resting phase before falling out and being replaced by new hairs.
With telogen effluvium, this system goes awry. After a stressful period, a large proportion of your hairs simultaneously shift to the resting phase. Six to twelve weeks later, they fall out. Not gradually, but in large numbers all at once.
It feels alarming, and that's understandable. But the mechanism is different from androgenetic alopecia (hereditary baldness), and that has major implications for what you can do about it.
What are the most common triggers?
Telogen effluvium almost always occurs after a trigger. The most well-known are:
Mental or emotional stress: a difficult period at work, a breakup, grief, financial problems. The body reacts to prolonged psychological pressure by adjusting the hair cycle.
Physical stress: severe illness, surgery, high fever, or a serious infection. During such a period, your body prioritizes recovery, not hair growth.
Nutritional deficiencies: a sudden low iron level, zinc deficiency, or a severely calorie-restricted diet. Crash diets are a known trigger.
Hormonal fluctuations: fluctuations in thyroid hormones or a low testosterone level can also play a role in men.
The specific thing about telogen effluvium is that delay: you only experience hair loss weeks or months after the actual cause. This sometimes makes it difficult to make the connection.
How do you distinguish it from hereditary baldness?
This is the question most men really want to answer: is this temporary, or am I going bald?
Pattern: Hereditary baldness follows a pattern. The hairline recedes at the temples, the crown thins, or both. With telogen effluvium, you lose hair all over your head, diffusely spread. No clear pattern.
Sudden versus gradual: Genetic hair loss is an insidious process over years. Telogen effluvium feels like a sudden increase in a short time.
Identifiable cause: Has it been going on for years, or is it new and started after something you remember? Telogen effluvium almost always has an identifiable cause, even if it only becomes clear in retrospect.
If you're in doubt, visiting your GP is the surest way. A blood test can rule out nutritional deficiencies, and a dermatologist can assess which phase your hairs are in.
How long does it last?
In acute telogen effluvium, caused by a one-off event, the shedding period lasts an average of three to six months. After that, hair growth recovers spontaneously, provided the trigger has disappeared.
Full recovery, where hair density returns to its previous level, usually takes six to twelve months after the shedding stops.
There is also a chronic form, where hair loss lasts longer than six months. This requires more attention and is less predictable.
What can you do?
Telogen effluvium usually resolves on its own. But "on its own" doesn't mean you can't do anything.
Address the trigger. If stress is the cause, addressing sleep, relaxation, and recovery helps more than any product.
Check your diet. Ensure adequate iron, zinc, and protein. Not as a supplement just to do something, but because deficiencies can prolong shedding. If in doubt, request a blood test.
Support your hair follicles. During the recovery period, products that stimulate blood flow to the scalp can support the recovery process. Hairborn's Growth Serum contains ingredients like Redensyl and Procapil that support the hair follicle and can promote the transition to the growth phase, without the side effects that medication sometimes has.
Be patient. Hair growth is slow. Even if you do the right things, you'll only notice results after months.
What doesn't work
Biotin is listed as an ingredient on many hair products, but supplementation only works if you have a demonstrable biotin deficiency, and that's rare. At normal levels, extra biotin has no proven effect on hair growth.
Anti-stress shampoos and complex supplements that promise to regrow hair are largely marketing. The hair grows back when the body recovers, not thanks to a shampoo.
Hereditary baldness as an underlying risk
One nuance to mention: sometimes someone already has a genetic predisposition to baldness, and a period of telogen effluvium acts as an accelerator. Hairs that might normally have lasted for years fall out sooner.
Even if telogen effluvium fully recovers, an underlying pattern of hereditary baldness that was always there may become visible. This is relevant to know, because the approach is then different.
In short
Hair loss due to stress, telogen effluvium, is recognizable by diffuse shedding all over the head, almost always with an identifiable trigger three to six weeks earlier. In most cases, it resolves on its own once the underlying cause is removed. It differs fundamentally from hereditary baldness, although both can be present simultaneously.
If you're unsure about the cause, don't settle for an assumption. A visit to the GP or dermatologist takes an hour and provides much more certainty than hours of searching online.