Explain the terminal Length concept to me

[khrystyne572]

So I've been reading here about Terminal Length, and that after a certain period of time your hair enters telophase and stops growing.

But, your hair eventually comes out of telophase and begins growing again right? Or not? What triggers telophase? The weight of your hair on the follicle, or just some mysterious time clock hidden in the genes? Is it preset like leg hair to just grow a certain amount and be done?

How long will hair sit in telophase and have no growth? Lets say that a person's hair is on an eight year cycle- meaning it grows for eight years and then hits telophase- does that mean it grows for eight years and then takes an eight year break?

I'm confused.

[WildEagle]

Oooh great question Khrystyne! Unfortunatly I don't have these answers at all, so will be keeping an eye on this thread.

I just wanted to add another question to your post that maybe someone could answer too...
Is there an 'average' terminal length in which the majority of people have? Would most stop at around the same length, and then very few have the special genes to grow longer?
If so, what is the average terminal length?

[pixiedust]

I got this one. Give me a second to type up an explanation ;)

ETA:

There are three phases of hair growth, the Telogen phase being the last one. A hair goes through all three phases (and they all do, eventually) and then releases from the follicle, or the 'root', which is a tiny 'pocket' that hairs grow out of (like your pores). Each hair follicle is said to go through about 20 or so of these growth cycles in a life time (EDIT: this is questionable information) The cycles of growth are:

Anagen
The anagen phase is known as the growth phase. It begins in the papilla (this is basically another word for the hair follicle or hair root) and can last around eight years. The longer the hair stays in the anagen phase, the faster and longer it will grow. During this phase, the cells in the papilla divide to produce new hair fibers, and the follicle buries itself into the dermal layer of the skin to nourish the strand. About 85% of the hairs on one's head are in the Anagen phase at a given time.

Catagen
When the anagen phase ends, the catagen phase begins. The catagen phase, also known as the transitional phase, allows the follicle to, in a sense, renew itself. During this time, which lasts about two weeks, the hair follicle shrinks due to disintegration and the papilla (or root) detaches and "rests", cutting the hair strand off from its nourishing blood supply. Although the hair is not "growing" during this phase, the length of the hair fibers continue to increase when the follicle pushes them upward. These hairs usually don't shed, but they don't "grow" as fast as hairs in the Anagen phase. This is the shortest cycle, lasting about a month, and only about 3% of hairs are usually in this cycle at once.

Telogen (the one you're talking about)
During the telogen, or resting, phase the hair and follicle remain dormant anywhere from 1–4 months. 10%-15% of the hairs on one's head are in this phase of growth in any given time. 70 percent of hair prematurely can enter a phase of rest, called the telogen phase. Three months later, these hair begin to fall. The Anagen phase begins again once the Telogen phase is complete. The preceding hair strand is pushed up and out by the new, growing strand. The process causes the normal hair loss known as shedding.

That was all mostly stolen from wiki, but I edited it because the article wasn't 100% factual (in comparison with my book on Trichology) and I wanted to make sure it was a little easier to understand.

These are some of the things that affect hair growth cycles:

1. Stress, diet, sleeping habits, medications, illnesses, body weight, etc etc. I can't go much into detail about how because this post would become entirely too long, but if you dig in the forums for a little while you can find out more. Personally, I've only found that stress and diet have been significant factors in my personal growth rate/quality of hair (I am slightly underweight and it hasn't slowed my growth, caused my hair to thin or become brittle etc).

2. The harsher you are with handling hair, the more likely it is to prematurely enter the telogen phase (aka, pulling out hairs while combing/brushing that aren't quite ready to fall) and this sort of relates to my next point...

3. While haircuts and breakage don't necessarily effect your growth cycles, they shorten hairs that should technically be longer, which can appear to be "premature shedding" when really, a hair is falling out at a terminal length of 12" and not, say, 40" because it was cut/broken several times throughout its growth cycle. This is why many people who first start on LHC (or women in general) think that they have a terminal length that is much shorter than it really is.

4. Chemical and Mechanical damage. See number 3.

5. Genetics and Hormones have been said to be a big factor in how long a hair stays in the Anagen phase. Science has found in studies that Estrogen (female hormone) has a lot to do with having healthy, thick hair. Certain male sex hormones (both men and women have them, in varying amounts) like Androgens (sometimes called DHT) in excess in the body can cause hair to fall and not grow back, for some reason; More often than not, it seems to be a lack of estrogen rather than an excess of Androgens that causes hair to fall prematurely. This is why you see a lot of little girls with baby fine, super thin hair. This premature hairfall is called Loose Anagen Syndrome, where hair falls or can be pulled out in all growth phases. Usually, this corrects itself with age. If it doesn't, things can be done about it to reduce premature shedding (ie, careful handling, birth control, etc etc)

Anyways, most people's terminal length (if I remember correctly) is somewhere around 45" or tailbone. Some women can grow their hair longer (I couldn't tell you why, there's not really any science-proven reason yet to my knowledge.) Keep in mind that a woman who is 5'11 might have the same length of hair as a woman who is 5'0 tall (for example, 40" in of hair) but the tall woman's hair would appear shorter, say TB length, where the shorter woman has less height; thusly the same length on her would appear to be, say, knee length. For example, Crystal Gayle is a famous country singer who is known fr her very very long hair, but she IS only 5'2. I'm not saying that this is ALWAYS a factor in terminal length, but it's something to think about.

Wow, that was really long, sorry. Hopefully this was helpful (If you can bear to read it all, haha.)

Anybody who sees something in here that they want to ask questions about, feel free. Also, if I missed something or if information is incorrect, let me know and I'll correct it asap. Thanks (:

[mathnerd]

I'm kind of interested by this topic as well. Will wait for your explanation too pixiedust! lol

[Nevvie]

You have to think of each individual strand (and follicle) of hair as a separate entity. Each strand has a life cycle. They don't all grow at the same rate or fall out at the same time. At any given time usually about 85% of your follicles are in various stages of the growing phase, anywhere from not yet breaking past the skin on your scalp to the longest strands and everywhere in between.

Anagen Phase is the growing phase. This phase lasts for years, but each person is different. Catagen Phase (which only lasts a week or two) is an in between phase where the follicle shrinks and starts to break apart. Telogen Phase is the resting phase and the end of a follicles life cycle. This last phase usually only lasts for a few weeks. When it's over the strand of hair will either fall out or be pushed out by the new strand of hair that has begun growing in the follicle.

Everyday you shed a few of the oldest hairs and gain a few brand new ones. Terminal length is the maximum amount of growth that a strand can reach before falling out and being replaced. Some strands will grow slightly faster or slower than others and some strands are considerably older than others, which is why not every hair on your head is the same length.

[ilovelonghair]

Each hair follicle goes through about 20 or so of these growth cycles in a life time (but this is just an estimation.)


So if you'd wax your legs 20 times (with letting the hair grow back fully each time after) would mean you can get rid of leg hair forever? No wait, that wouldn't make sense, leghair doesn't even grow that long so each phase is much shorter, that would mean you'd run out of leghair pretty soon in life. Not true!

I'm trying to calculate something and I am terrible with numbers, so if anyone can help please :) :
the average person (man or woman) can grow their hair 45", I assume thats LHC lenght and not the actual lenght of a single strand. From what I could find out from Google, average hair grows 70-90 centimeters (27.6"-35.4") before it falls out. And most hair grows 1 centimeter a month. So wouldn't an average person 'run out' of hair before they die, if you calculate how often a hair can grow, how many years it grows and the phases in between? (using the numbers provided)

[Juicematic]

Very interesting! I've seen terminal length on some members stats and wondered about it. Thanks to everyone for the excellent explanations.

[spidermom]

Once a hair stops growing, it doesn't start growing again. It sheds out.

The 3 phases of hair growth have already been explained very well. You will notice that most of the people who have terminal length hair have a lot of taper at the ends. Sometimes there is one longest hair because that one either has a longer growth cycle than other hairs, grows faster than other hairs, or both.

I did have a roommate in the past whose hair never got longer than BSL in all the 8 years that I knew her. She didn't cut it and she didn't abuse it, so I can only conclude that most of her hairs had growth cycles that ended at about 3 years. She didn't have much taper either. It was kind of strange, and she was so frustrated because she wanted to have really-really-really long hair. It just wasn't in the genes for her.

[WildEagle]

Thanks Pixiedust for all that helpful info...the OP got me very curious about this!
I understand a whole lot more now, thanks :)
:thumbsup:

[Kiwiwi]

@pixiedust

That was super interesting, thank you so much! ^_^

[pixiedust]

So if you'd wax your legs 20 times (with letting the hair grow back fully each time after) would mean you can get rid of leg hair forever? No wait, that wouldn't make sense, leghair doesn't even grow that long so each phase is much shorter, that would mean you'd run out of leghair pretty soon in life. Not true!

I'm trying to calculate something and I am terrible with numbers, so if anyone can help please :) :
the average person (man or woman) can grow their hair 45", I assume thats LHC lenght and not the actual lenght of a single strand. From what I could find out from Google, average hair grows 70-90 centimeters (27.6"-35.4") before it falls out. And most hair grows 1 centimeter a month. So wouldn't an average person 'run out' of hair before they die, if you calculate how often a hair can grow, how many years it grows and the phases in between? (using the numbers provided)

I read a while back on some informational page (from some sort of 'scientific' source if I remember correctly) That it was about 20 times each follicle goes through this cycle. I would agree with you that it wouldn't make a lot of sense because I know many women who have waxed their legs AT LEAST 20 times, and still wax their legs because the hair grows back. However, The kind of hair that grows from your head opposed to other body hair are not necessarily the same kinds.

I got the 45" statistic from these forums, so it's probably LHC length, as in length from the front hairline to the longest length of the hemline. That makes 27.6"-35.4" sound pretty much correct (give or take of course).

I am unfortunately also really bad with numbers, so if anybody likes to figure out these types of calculations, please let us know! :D

Meanwhile, I'll edit the top post a bit.

[pixiedust]

Once a hair stops growing, it doesn't start growing again. It sheds out.

The 3 phases of hair growth have already been explained very well. You will notice that most of the people who have terminal length hair have a lot of taper at the ends. Sometimes there is one longest hair because that one either has a longer growth cycle than other hairs, grows faster than other hairs, or both.

I did have a roommate in the past whose hair never got longer than BSL in all the 8 years that I knew her. She didn't cut it and she didn't abuse it, so I can only conclude that most of her hairs had growth cycles that ended at about 3 years. She didn't have much taper either. It was kind of strange, and she was so frustrated because she wanted to have really-really-really long hair. It just wasn't in the genes for her.


Thanks Pixiedust for all that helpful info...the OP got me very curious about this!
I understand a whole lot more now, thanks :)
:thumbsup:


@pixiedust

That was super interesting, thank you so much! ^_^


Very interesting! I've seen terminal length on some members stats and wondered about it. Thanks to everyone for the excellent explanations.

Thanks guys, and you're welcome :D Always happy to share as much hair information as possible!

[Chetanlaiho]

Estrogen (female hormone) has a lot to do with having healthy, thick hair. Certain male sex hormones (both men and women have them, in varying amounts) like Androgens (sometimes called DHT) in excess in the body can cause hair to fall and not grow back, for some reason; More often than not, it seems to be a lack of estrogen rather than an excess of Androgens that causes hair to fall prematurely. This is why you see a lot of little girls with baby fine, super thin hair. This premature hairfall is called Loose Anagen Syndrome, where hair falls or can be pulled out in all growth phases. Usually, this corrects itself with age. If it doesn't, things can be done about it to reduce premature shedding (ie, careful handling, birth control, etc etc):
Hmm, I suspect I might actually have a lack of estrogen (no scientific proof, just some theories I read that apply to me) would that contribute to me having thinner hair? (Does anyone know if there's a way to test this?)

I've been afraid to go on birth control because of what I've heard about thinning hair but from what it sounds like it might actually help? xD

Also major thanks for typing all that out! I enjoyed reading it a lot ^_^

[Mesmerise]

Hmm, I suspect I might actually have a lack of estrogen (no scientific proof, just some theories I read that apply to me) would that contribute to me having thinner hair? (Does anyone know if there's a way to test this?)

I've been afraid to go on birth control because of what I've heard about thinning hair but from what it sounds like it might actually help? xD

Also major thanks for typing all that out! I enjoyed reading it a lot ^_^

I am also thinking that I could be low in estrogen! Especially as the front of my hair seems noticeably thinner and patchier. I wonder if there's something one could take that would help the body produce a normal amount???

[pixiedust]

Hmm, I suspect I might actually have a lack of estrogen (no scientific proof, just some theories I read that apply to me) would that contribute to me having thinner hair? (Does anyone know if there's a way to test this?)

I've been afraid to go on birth control because of what I've heard about thinning hair but from what it sounds like it might actually help? xD

Also major thanks for typing all that out! I enjoyed reading it a lot ^_^


I am also thinking that I could be low in estrogen! Especially as the front of my hair seems noticeably thinner and patchier. I wonder if there's something one could take that would help the body produce a normal amount???

There's a lot of controversy on birth control and people losing some hair when they go off it. I personally am scared to death of taking it. shudder:

It's been said that eating soy is good for hair growth, maybe it has something to do with the estrogen it contains?

[ilovelonghair]

I did have a roommate in the past whose hair never got longer than BSL in all the 8 years that I knew her. She didn't cut it and she didn't abuse it, so I can only conclude that most of her hairs had growth cycles that ended at about 3 years. She didn't have much taper either. It was kind of strange, and she was so frustrated because she wanted to have really-really-really long hair. It just wasn't in the genes for her.


That's where the 20 times gets really scary: with such a short cycle she'd run out of hair real quickly! The people I know who have short cycles are seniors now and have a lot of hair, so I think we shouldn't worry too much :)


There's a lot of controversy on birth control and people losing some hair when they go off it. I personally am scared to death of taking it. shudder:

It's been said that eating soy is good for hair growth, maybe it has something to do with the estrogen it contains?


When I went off it nothing happened, but I loose hair from stress. Hair would of course grow back. I think that with going off the pill it might be a bit similar as a post natal shed? And it will grow back. But I know enough people who never had any hair loss after stoping the pill, so there's hope :)
And what about our older members here with lovely hair who are in their menopause? I think there must be so many more factors regarding hair loss/no hair loss than just hormones.

If we worry about it all: we'll loose hair! better not to :p

[spidermom]

That's where the 20 times gets really scary: with such a short cycle she'd run out of hair real quickly! The people I know who have short cycles are seniors now and have a lot of hair, so I think we shouldn't worry too much :)

:p

Hmmmmmmmm; I didn't think of it that way, but it's a good point. 20 x 3 is only 60. It sounds like she could end up with very thin hair, if any hair at all.

Or she could have very slow growing hair. Maybe it takes her hair 6 years to get to BSL, and 20 x 6 would mean she wouldn't run out of hair until she's 120. I think most of us won't have hair after 120 years.

[ilovelonghair]

I think the 20 isn't true, plus it would be different for each person AND for each single hair on someone's head. Some people past hundred still have some hair left.
I try not to worry about running out of hair, there are always wigs! Now those can be fun: a different hair color each day of the week!

[spidermom]

I have seen a few old women around with more scalp than hair. But I'm pretty sure you're right that 20 is an average, not an absolute.

[Cowgirl16]

Thank you pixiedust, great information :)

[torrilin]

Very interesting! I've seen terminal length on some members stats and wondered about it. Thanks to everyone for the excellent explanations.

If you're thinking of someone like Trolleypup...

He's got fairly coarse hair. He also takes care of it about as gently as I take care of my fine hair, so no heat, no dye, and no rough handling. That means he is not breaking hairs often, and he doesn't have a lot of split ends. When he does have split ends, he's mentioned that he takes care of them via search and destroy. Despite all that, his hair has been constant at thigh length for at least 5-6 years, probably a good bit more than that.

The key there is the constant length and lack of trims. If he'd been at thigh for a year with no growth? Maybe it's terminal, maybe not. Two years? Terminal is a lot more likely. At 6 years with no growth, it's pretty certain he's at terminal.

That is why the first question I ask if someone is freaking out about being at terminal is how often they trim. Chances are they trim way more often than I do.

[ilovelonghair]

You're right about coarse hair, less breakage, longer teminal length, makes sense :)

[Littlewing13]

Bumping this, as I've noticed a few people asking, & pixiedust's explanation is fantastic.

[jacqueline101]

Its when your hair stops growing. It has a lot of taper to it. Most people reach that phase around classic length.

[Merlin]

When your hair gets really long Skynet sends a robot back from the future to trim your ends while you're asleep so it never seems to get any longer...

[MonaMayfair]

When your hair gets really long Skynet sends a robot back from the future to trim your ends while you're asleep so it never seems to get any longer...

I KNEW there must be a logical explanation, lol!

[WaitingSoLong]

I missed this original thread and glad someone resurrected it. It was an interesting read but I have some comments...


I am also thinking that I could be low in estrogen! Especially as the front of my hair seems noticeably thinner and patchier. I wonder if there's something one could take that would help the body produce a normal amount???

Chastetree Berry (sold under name brand Vitex) is an herb that is supposed to regulate female hormones, regardless of whether you are high or low in whatever, it is said to balance them out. I took this for an extended period when I was going through infertility and never noticed any changes in my cycle or anything (PMS) but hormones were not my real issue. We just didn't know that then. I know this is a bit late to offer this info.


! The people I know who have short cycles are seniors now and have a lot of hair, so I think we shouldn't worry too much :)

When I went off it nothing happened, but I loose hair from stress. Hair would of course grow back. I think that with going off the pill it might be a bit similar as a post natal shed? And it will grow back. But I know enough people who never had any hair loss after stoping the pill, so there's hope :)
And what about our older members here with lovely hair who are in their menopause? I think there must be so many more factors regarding hair loss/no hair loss than just hormones.


Regarding the first sentence, I have seen some elderly women with some extremely thin hair. This accounts for the "old lady" hairdo that is so often seen. Short with a perm seems to be the best way to cover up thinning hair in older women. I have always been afraid this would happen to me.

Regarding hormones and hair shedding, every pregnancy book I ever read says a lot of the same thing "scientists are not sure why _________" fill in the blank. One example would be "why some women get linea negra". I did during one of my pregnancies, and never did again. They *think* it has something to do with hormones, because hormones change so drastically during pregnancy, but they are not sure. Really, they just don't know. There is no bar standard for all pregnancies, and every woman reacts differently to BCP's. Some can't take them at all. Our bodies are a rightly woven hormonal system. Disrupt one, you tilt the balance and something else is likely to fall off, metaphorically speaking. Ask anyone who has ever had their thyroid removed how much THAT hormone affects everything else. The more current research I am reading is largely related to insulin. Scientists are learning that insulin plays a much larger role in hormonal regulation than just controlling sugar. I could really get off topic here and talk about why people can't lose weight with dieting and exercise all because of insulin. See Gary Taubes for that.

But every decade some "new" research comes out that blows away the old. Like eggs used to be good for you, then they were bad for you, then they were good for you. It is hard to really place your chips on any one set of research data. Talk about faith, science is the new religion. sigh.


Or she could have very slow growing hair. Maybe it takes her hair 6 years to get to BSL, and 20 x 6 would mean she wouldn't run out of hair until she's 120. I think most of us won't have hair after 120 years.

Run out...but how much thinning takes place? No doubt hair thing with age, regardless of gender. My daughter is 13. She has run with the same friends since 1st grade and all the little girls I see (referring to an earlier reference to little girls with baby fine hair) have super thick hair. My daughter has MY hair basically only twice as thick. I know my hair was thicker when I was younger. Just observations. I have no clue what it all means. LOL


If you're thinking of someone like Trolleypup...


That is why the first question I ask if someone is freaking out about being at terminal is how often they trim. Chances are they trim way more often than I do.

Speaking of Trolleypup...how much estrogen to men have?

Trimming. Why do people think their hair stopped growing when they trim every 6 weeks?


Its when your hair stops growing. It has a lot of taper to it. Most people reach that phase around classic length.

I was always under the impression that Classic was the traditional terminal length.

[dollyfish]

When your hair gets really long Skynet sends a robot back from the future to trim your ends while you're asleep so it never seems to get any longer...

Goes well with the phrase "Terminal" :guns:

[bte]

This has been a very interesting thread, and thanks to pixiedust for such a good and detailed explanation.

I have been at terminal length for about 14 or 15 years, not having trimmed or cut since 1994, and having experienced no extra growth since some time in 1997 or 1998 when I reached around apl. Sounds a little vague, but it's not easy to pinpoint the day when I last noticed any extra growth exactly. I don't think damage is a significant factor, as I try to be careful.

So yes, terminal length varies a lot, and it is possible to have new growth even after years of stalling (in theory even for me, but I doubt it will happen). Terminal length is yet another way in which we are all different.

[Littlewing13]

When your hair gets really long Skynet sends a robot back from the future to trim your ends while you're asleep so it never seems to get any longer...

Brilliant! lol

[ravenheather]

Great news about classic being the average terminal length. I could totally live with classic.

[lmfbs]

Why do many men tend to bald more quickly, then? Is it that their terminal length is much shorter so they use their 20 cycles more quickly? Obviously that doesn't apply to all men.

This makes me worried about my hair pulling. Am I going to run out of hair cycles before I die? :(

[Tisiloves]

Why do many men tend to bald more quickly, then? Is it that their terminal length is much shorter so they use their 20 cycles more quickly? Obviously that doesn't apply to all men.

This makes me worried about my hair pulling. Am I going to run out of hair cycles before I die? :(

It's because their DHT gets out of whack. Also your hair pulling won't actually shorten your cycles, a lot of the time pulled hair actually snaps off rather than pulls out anyway.

[WaitingSoLong]

I always heard that by repeatedly pulling a hair it will eventually fail to grow back. This was in reference to facial hair (plucking eyebrows and whatnot) but I am hear to say I have been plucking and plucking for years and years and it always grows back! It is like the leg waxing thing mentioned earlier. I think it is urban legend.

Maybe hair goes through the whole cycle and AVERAGE of 20 times before age and genetics takes over and just keeps it from growing back. In which case it is not a 20-time bomb, but it will grow back infinite number of times until something else tells it not to...age or whatever. Just thinking!

[GoblinTart]

I always heard that by repeatedly pulling a hair it will eventually fail to grow back. This was in reference to facial hair (plucking eyebrows and whatnot) but I am hear to say I have been plucking and plucking for years and years and it always grows back! It is like the leg waxing thing mentioned earlier. I think it is urban legend.

Maybe hair goes through the whole cycle and AVERAGE of 20 times before age and genetics takes over and just keeps it from growing back. In which case it is not a 20-time bomb, but it will grow back infinite number of times until something else tells it not to...age or whatever. Just thinking!

Aha! I knew that whole pluck it and the follicle dies was a myth! I've been plucking my eyebrows 2x a week for over 13 years, yet the same hairs keep growing back. And theyre just as thick as the rest of my eyebrow hairs. Grrrr....

[Tisiloves]

I always heard that by repeatedly pulling a hair it will eventually fail to grow back. This was in reference to facial hair (plucking eyebrows and whatnot) but I am hear to say I have been plucking and plucking for years and years and it always grows back! It is like the leg waxing thing mentioned earlier. I think it is urban legend.


If you pluck hairs enough you can damage the follicle so that they never grow back.

[RapunzelKat]

Does anyone know how it was determined that classic is the average length most people can achieve? Or how the average length of the life cycle of the hair is determined? I was curious because on average most people don't let their hair grow to terminal length and keep it trimmed so that the oldest part of the hair is always being cut off. (At least this is true where I live ;))

Hope those questions make sense :lol: Couldn't quite figure out how to word it.

[Silverbrumby]

Does anyone know how it was determined that classic is the average length most people can achieve? Or how the average length of the life cycle of the hair is determined? I was curious because on average most people don't let their hair grow to terminal length and keep it trimmed so that the oldest part of the hair is always being cut off. (At least this is true where I live ;))

Hope those questions make sense :lol: Couldn't quite figure out how to word it.

I thought it depends on you ethnic background and genetics. I also thought classic length was not the norm for some groups of people and individuals. No one in my family has ever had classic length. Not even my grandmother who never cut her hair (even when she was younger).

[Inozz]

This was very helpful. Thanks for explaining it Pixiedust.