Summer versus Winter Growth

[florenonite]

I've been keeping track of my hair for the better part of three years now, and I've noticed consistently that it grows an inch a month in the summer, then half an inch for the rest of the year, sometimes slowing almost entirely in the winter. I know I'm not the only one who experiences faster growth in the summer; it's a pretty common phenomenon. What this makes me wonder, though, is if it would be possible to treat hair year-round in such a way that it produces similar effects to summer weather.

There are two elements to this, of course. The first is that it is necessary to determine why hair grows faster in the summer. I did some googling around and couldn't find anything conclusive, though several I did find several feasible hypotheses. The second element is replicating these circumstances year-round.

Anyone have any ideas about either of these things?

From what I've read, possibilities include heat, humidity, and exposure to sunlight. For the first, I wonder if maybe blowdrying the scalp only (stopping before hair is fully dry) might help by delivering heat to the scalp. Humidity might increase with a humidifier or if people live in damper locations. Exposure to sunlight could be mimicked either with lightbulbs that mimic UV rays or increased dietary intake of vitamin D, or indeed even focussing on going outside during daylight.

I think it would be interesting if we could get a group of us together to do a controlled study to see if it is possible to replicate the effects of summer on hair growth throughout the year. If you find your hair tends to grow faster in the summer than the winter, would you be interested in trying out one of the things listed above (or something someone else comes up with) to see if it makes a difference?

[bistin]

I was trying to come together with a way to ask these same questions, but I'm not one with words. Lol. I'm glad someone finally posted something about this. I don't go outside much in the summer but my hair grows faster anyway.

[bistin]

Random thought as well. I tend to be more active and drink lots more water in the summer, I'm not sure if that could be a factor as well.

[florenonite]

Random thought as well. I tend to be more active and drink lots more water in the summer, I'm not sure if that could be a factor as well.

Yeah, I considered that, though I've had vastly differing amounts of physical activity each of the past four summers and still had increased growth. I also drink primarily water (and tea) during the year, so not much of a change there :shrug:

It could still be a contributing factor, though, for others, and worth investigating.

[my2cats1]

This topic has facinated me for a long time -- surprised there hasn't been more research on it.

I read somewhere that growth is influenced by changes in hormone levels, but I'm not sure how/if summertime factors affect that.

Anyway, here is a link from The Beauty Brains you might find interesting:

http://www.thebeautybrains.com/vanilla/comments.php?DiscussionID=1363

[my2cats1]

Sorry, I just realized the above link may not work for everyone. It is a forum in which the topic was raised, and someone posted these links:

one reference...http://www.ncbi.nlm.nih.gov/pubmed/2003996

: http://www.ncbi.nlm.nih.gov/pubmed/20098801
here's one that analyzes the role of melatonin (our sleep hormone that is activated in the dark) http://www.ncbi.nlm.nih.gov/pubmed/19957072
here's one that talks about peaks in telogen hairs in the summer, specifically in women with no conditions otherwise affecting hair growth: http://www.ncbi.nlm.nih.gov/pubmed/19407435
here they talk about the ``hair eclipse phenomenon`(ive never heard of that before) http://www.ncbi.nlm.nih.gov/pubmed/18494912

[Lexy]

It can't be humidity and it can't be increased activity. In Northern California we get no humidity to speak of, and my hair still grows faster in the summer. Also my activity level is more or less consistent all year long, and as I said, faster growth in the summer.

[florenonite]

Thanks for the links, my2cats1.

Alex: I think I might actually have less activity in the summer, because I have access to a car :p

[irisheyes]

Makes me wonder about hair growth rates in the tropics, or places where the differences in seasons are not as extreme as in northern climes.

[melikai]

I have an almost identical growth pattern. I think that it may be something that goes deeper though, into physiology, genetics and so on, so I don't think it would be possible to replicate year-round.

[Rebelkat]

I wonder if the produce during the summer affects our hair differently from winter produce. I would imagine that the colder weather has an effect on the soil and the nutritional content of the soil would affect the nutritional content of the produce. That's just a guess, though.

I personally believe vitamin D makes a big difference. A vitamin D deficiency can cause serious physical and psychological side effects. One of the symptoms of a D-deficiency is hair loss, so it would make sense that a surplus of D could cause rapid hair growth. :hmm:

[florenonite]

I wonder if the produce during the summer affects our hair differently from winter produce. I would imagine that the colder weather has an effect on the soil and the nutritional content of the soil would affect the nutritional content of the produce. That's just a guess, though.

However a lot of what we (general we) eat is imported anyway, though it's possible that people tend to eat more local stuff in the summer, which would be fresher. I know I personally eat more local food in the summer because fresh local fruit and veg actually exist in the summer :lol:



I personally believe vitamin D makes a big difference. A vitamin D deficiency can cause serious physical and psychological side effects. One of the symptoms of a D-deficiency is hair loss, so it would make sense that a surplus of D could cause rapid hair growth. :hmm:

I've been thinking this, too, but then I haven't actually spent a whole lot of time outside this summer. Maybe the difference is it's less cloudy than it is at uni in Britain :p You're right, though, that vitamin D deficiency manifests itself in a whole host of different ways. It's also assimilated more effectively from sunshine than from the diet, though you should make enough in the summer to do you the entire year.

[Coriander]

I actually have better growth in the winter. I'm weird like that. :lol:

[Darkhorse1]

I find my hair grows less in the summer and way more the minute the weather gets cooler--I figure it's a survival thing---more hair to keep you warm, less to keep you cool?

I would venture to guess it has more to do with metabolism. If some people don't handle heat well, perhaps their metabolism is faster in the summer than winter?

This is a theory I have after having two really bad viruses with high fevers, and with both cases, I know my metabolic rate was increased because I grew hair lightning fast, as well as fingernails grew and leg hair.

However, I don't recommend getting a high fever as a good way to grow hair ;)

[schweedie]

I find my hair grows less in the summer and way more the minute the weather gets cooler--I figure it's a survival thing---more hair to keep you warm, less to keep you cool?
This was what I was told when I was sad after my latest chop - that my hair would grow quickly the first couple of months since hair grows faster when it's cold, to keep you warm. I've never actually thought to measure and compare, though. Interesting that so many experience more growth in the summer.

[jackiesjottings]

I have the opposite :(( I have a summer stall and I have no idea why. My hair grows fasest between about November and May. I dont like heat but I somehow doubt that would influence my hair growth! measured last night and have had hardly any growth in the last 6 weeks :(

[CherrySilver]

I suspect that faster hair growth in the summer may be related to the heat. Hotter temps will increase body surface temps leading to increased micro-circulation (e.g. scalp). This may produce increased blood flow to the scalp which may lead to faster growth.

I've also noticed that using a sauna on a regular basis has really increased my rate of growth. In the winter, I've almost slowed to a complete stall. However, going in the sauna has helped tremendously. Using a far-infrared sauna was a quantum leap over a regular sauna regarding hair growth, however.

All of the above leads me to believe that higher temps (and possibly sunlight) may assist with hair growing faster during the summer.....

[florenonite]

I actually have better growth in the winter. I'm weird like that. :lol:

SoCal has seasons? :p


I find my hair grows less in the summer and way more the minute the weather gets cooler--I figure it's a survival thing---more hair to keep you warm, less to keep you cool?

I would venture to guess it has more to do with metabolism. If some people don't handle heat well, perhaps their metabolism is faster in the summer than winter?

This is a theory I have after having two really bad viruses with high fevers, and with both cases, I know my metabolic rate was increased because I grew hair lightning fast, as well as fingernails grew and leg hair.

However, I don't recommend getting a high fever as a good way to grow hair ;)

The metabolism thing is interesting. My body doesn't like heat; in contrast I'm always cold in the winter so perhaps my body is expending more energy keeping me warm.

[Lexy]

I have an almost identical growth pattern. I think that it may be something that goes deeper though, into physiology, genetics and so on, so I don't think it would be possible to replicate year-round.

I was thinking something like this too, but couldn't come up with the words when I needed them. :lol:

[HairColoredHair]

I find I grow way more Spring, Winter, and Autumn... In the summer I'm miserable, tired, and grouchy, and my hair is too.

[dropinthebucket]

I was thinking the same thing - there must some info. somewhere on hair growth rates in different climates, and whether those living in tropical and subtropical climates experience faster hair growth? It sounds counter-intuitive, evolutionarily speaking - more hair, and more body hair, is needed in warmer climates - but then, there are other factors too, including sunshine and vitamin production, melanin, and so on. So I dunno - would be interesting to find out!

[dropinthebucket]

A decent hair site in general, and some info. on hair growth and seasonal changes:

http://www.hairinformation.com/hair-growth/

Also this interesting article from the British Journal of Dermatology on human hair and seasonal growth patterns:

http://www3.interscience.wiley.com/journal/119341565/abstract?CRETRY=1&SRETRY=0

[Sammich]

I realise my hair grows much faster in spring and almost summerish than in the winter, winter I seem to get little stalls... hmm, but don't quote me on that! I'm not totally sure, I'll be checking out my growth and keep you posted. ;)

[harpgal]

http://sbrjournal.net/currentissue/articles/Hair/Hairgrowth.htm

[ericthegreat]

I definitely think that temperature/ amount of sunshine/ also the types of local foods that you eat effects the growth rate of your hair. In the summer, the temperature and the amount of sunlight is the highest it will be for the entire year. Local fruits and vegetables are grown during the summer, and so the kind of nutrition we get during the summer is usually much better. Even our own bodies produce more vitamin D through our skin over the summer.

Also, I see many women who hail from tropical countries (I'm thinking specifically of Indian women and also women from Latin American countries like Brazil and Colombia) who have extremely thick, full, lush long hair. I think if we were to do a study of average human hair growth, we would find that people in tropical countries tend to grow their hair faster than people who live in colder climates.

[spidermom]

I'm pretty sure it has something to do with hours of daylight, but for you contrary-wise sorts - who knows?

[florenonite]

Thanks for the links, dropinthebucket and harpgal. I don't have time to read them right now, but I will shortly.

I also read something about how hair grows faster in the summer to protect the scalp from the sun. Others here have also speculated that Indian women tend to have thick hair for that very reason. So that would suggest sunlight, as spidermom mentioned. ETA: Maybe some of the contrary folk live in areas where there isn't a huge difference in daylight between summer and winter?

[harpgal]

I'm pretty sure it has something to do with hours of daylight, but for you contrary-wise sorts - who knows?LOL! For this very reason, my lips are zipped. :D

[HairColoredHair]

Thanks for the links, dropinthebucket and harpgal. I don't have time to read them right now, but I will shortly.

I also read something about how hair grows faster in the summer to protect the scalp from the sun. Others here have also speculated that Indian women tend to have thick hair for that very reason. So that would suggest sunlight, as spidermom mentioned. ETA: Maybe some of the contrary folk live in areas where there isn't a huge difference in daylight between summer and winter?

(Or maybe they stay inside in the sunny months.) :lol:

[florenonite]

(Or maybe they stay inside in the sunny months.) :lol:

Perhaps, but I do that too :p