25-30 Hair Cycles Per Hair Follicle In A Lifetime?

[ovdw]

I have a question regarding a possible limited number of hair strands coming from each follicle during a lifetime. On several information websites it is stated that a human hair follicle on the head has a limited capabality of producing new hair strands that is restricted to an amount of 25-30. Considering a 2-7 years anagen phase for each hair follicle, one has enough hair for 50-210 years under healthy circumstances.

Hairloss explanation at such a website (http://www.norgilcanada.com/en/services-and-treatments/natural-cycles-of-hair.html):
In short, the elevation of alpha 5 reductase results in shortening of the anagen phase (growth phase) of hair and the deminution of hair in the growth phase. The duration of each cycle will diminish considerably and several cycle-years will pass in several months. Hair cycles, that should have lasted a lifetime, will be spent much more rapidly, and this will at first result in a lightening of the hair, and then in progressive total hair loss on large portions of the scalp.


If the above is true, I wonder why people (not all) do experience regrowth from medications like finasteride, dutasteride, minoxidil, etc.? If hair is gone or progressively miniaturized (i.e. participating in one of the last hair cycles the hair follicle is capable of producing), then regrowth would not be possible since the hair follicle should (almost) be exhausted?

Does anyone have an explanation for this? Can anyone verify or refute the postulated theory?

I would be really grateful!

Thanks in advance.

 

[biddybomb]

interesting, I can't add anything to the discussion but it makes me wonder how much damage we do to our hair on a daily basis if this is true. Everytime you pull a hair from ur head thats still in the growth phase would prompt the cell to produce another. Overtime this could drastically reduce the lifespan of the follicule. Maybe that is what causes tension alopecia.

 

[ovdw]

I don't know whether pulling a hair from your head will change the growth phase a hair follicle is in. Hair is just dead cells coming out of the follicle. I figure that pulling a hair doesn't change the growth phase of a follicle.

 

[Timekeeper]

The number a hair on a scalp can cycle depends on the health of the follicle and is not a set number after all eyebrow hair cycles a couple hundred times in a lifetime.The 25 to 30 times is pure speculation not based on science.

 

[Timekeeper]

As an add on to my previous comment I have contacted certain websites ( Norgil/ La Roche-Pasay) about the 25 to 30 estimate or limit on hair follicle production in a lifetime and they have never replied.It must be noted that they and others are trying to sell tablets or medications that supposedly lengthen the Anagen phase of the hair follicle so that you don't "use up" your follicle life. Baloney I say and so do world wide reputable sites such as Philip Kingsley,Institute of Trichologists and Harley who believe a follicle if healthy and not damaged produce hair throughout life. I have a friend who went through untold stress for years and a clinical biologist stated he had Telogen Effluvium coming and going many times so he was losing and recovering hairs for a few years until his issues were resolved. he has plenty of hair now but must have gone through many cycles!. A healthy follicle produces hair not estimates,does a follicle count how many times it produces a hair and then stops be logical nuff said.