Tuesday, 17 November 2009

Reader Questions: Hair Shedding

This question was emailed to me quite a while back by Alexis, here it is.............

I have a question. Can you do a post about shedding? I'm a member of various hair boards and a lot of the things people say about shedding just don't make sense to me. The problem is, I can't find any scientific information outside of "everyone sheds 50-100 hairs a day".

The main things I'd like addressed:

"I used X product (usually it's protein) and my shedding stopped completely"....I feel like that's impossible, even with garlic, because hair has to shed at some point. A related thing is "I stopped combing/brushing/using heat, etc. etc. and my hair stopped shedding, " or, "Now that I take care of my hair I never shed"...everybody sheds right?

I do think it is safe to assume that everybody sheds hair. Shedding is part of the normal hair growth cycle allowing a new hair to emerge from the follicle. Hair breakage is different from shedding and some hair products can stop breakage at least temporarily.

I don’t think hair shedding can entirely stop but some people do shed hair while it is still in the growing phase and this can sometimes be fixed with medication.

Alexis: How much shedding is "normal"? Is 50-100 per day the right range?

Actually the exact range is 34-180 per day. This figure comes from a mix of scientific studies, the exception to the rule are Thai women who have a very low range of shedding at 28-35 hairs per day.

The range you quoted is often accepted widely by scientists and actually comes from maths. It is estimated than on average we have about 100,000 individual hairs on the scalp. It is then calculated that a vast majority 85-90% of these are in the growing stage (known as anagen). Therefore approximately 10% of hair is in the resting or shedding phase. Then estimate the amount of hair actually shedding and you get 1 in every 1000 hairs in total. For a head of 100,000 hairs you get that magic number 100 hairs per day. (Journal of the Society of Cosmetic Chemists, pg 195-206, 1992)

Alexis: Is there a such thing as seasonal shedding?

Yes this does exist but it is quite varied. Some people have it and some don’t. Also the patterns don’t necessarily follow the same trend. One study reported seasonal shedding among some men with most hair fall at the end of summer and the beginning of autumn. (British Journal of Dermatology, pg 47-54, 2008).

Another interesting fact is that pregnancy can reduce hair shedding dramatically because the hormone combination is thought to prolong the growing phase of hair. This can push down shedding to as low as 15-20 hairs per day. (Journal of the Society of Cosmetic Chemists, pg 195-206, 1992)


  1. Great article. I definitely feel that some women get breakage and shedding confused. I'm like isn't shedding SUPPOSED to happen daily? LOL.

  2. Thanks for this i got really confused once after reading some articles that suggested hair shedding was somehow wrong and a sign of unhealthy hair. I changed my mind after reading more informative articles but it's still great that you've taken the time to write this!

  3. great post! I shed a lot cause I only comb my hair once a month

  4. Since I wear my hair up every day which means I brush it only twice a day (once in the morning before I style it and once in the evening when I take it down) I shed a lot more hair when I'm washing them which is normal considering that in the times where I was wearing my hair down every day I brushed it a lot more. Plus I'm only washing it every 4. day instead of every second day like I used to.

    I think if you doesn't take any medication, live on a healthy diet and treat your hair well you shouldn't have any problems with too much shedding.

  5. Interesting post....Do you know if we can you build up a "backlog" of shedding? I style my hair once a week - right now I've been doing twists and styling those into an updo. Do I still shed daily? I don't comb or do anything except moisturize the surface.

  6. @puregoldlady - yes your hair sheds daily regardless of how much or how little you handle it. It is programmed to shed those 50-100 hairs a day. If you don't style it for 5 days then you will have 250 to 500 shed hairs which will need to be removed. This you could call a 'backlog'.

  7. I have a question. Is there such a thing as product related shedding? I mean, can a shampoo or conditioner cause increased shedding? In forum people sometimes say that but is this possible from a scientific point of view? Thanks a lot for your answer!

    1. Not that I have read about. I have seen articles increased shedding due to medication or hormonal changes e.g pregnancy. I would be curious to know what product was associated with shedding - I would research it.

  8. Thanks for your quick reply, Jc. Unfortunately I've been using more than one new products recently. I just wanted to know if you have ever heard of something like product related shedding. I have been suffering from a seborrohic eczema but it was under control recently except for a little bit of itching from time to time. I will see my doctor next week to have this checked.


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