[Lynda (OP)]

I have a decent mop of hair - just covering my ears in what I can only describe as a shaggy bob type of style.    My hair is thick and in good condition.     

I washed my hair this morning with my usual organic shampoo and had a bath full of hair.   Is this seasonal?   I had brushed my hair prior to washing it to remove as much loose hair as possible.  It seems odd we lose our nice warm hair in cold weather!    I still appear to have all my hair - so there is nothing wrong - I have noticed this in previous years.

[RD]

The suprachiasmatic nucleus (SCN) in the brain influences hormone production, and itself is affected by day length, (the amount of light reaching the retina).

So winter-time, with shorter days, could affect hormone levels via the SCN. The altered  hormone levels could then affect hair growth.

Many aspects of mammalian behavior and physiology show circadian rhythmicity, including sleep, physical activity, alertness, hormone levels, body temperature, immune function, and digestive activity. Remarkably, all of these diverse rhythms are controlled by a single tiny brain area, the SCN

The SCN receives inputs from specialized photoreceptive retinal ganglion cells, via the retinohypothalamic tract.

http://en.wikipedia.org/wiki/Suprachiasmatic_nucleus

[Nizzle]

Hm, but then it's not logical that seasonal hair loss occurs in autumn is it?

It should happen in spring then I'd imagine.

[raptorguy]

We sometines need to question assumed relationships and follow the evolution of a variable to an environmental setting.

Firstly I have no idea about the reality or not of hair loss, thicker hair etc....but

- does thicker hair help prevent skin cancer. etc. when we have more sun exposure in summer?

-does thinner hair prevent less spread of parasite causing diseases whe we are huddled together in winter?

-why is less hair a body-temperture negative in northern climates? People have had well evolved brains for hundreds of thousands of years and know to put on a hat. Taking off a hat allows for safer heat release when a body becomes hot due to physical activity in winter (I know, I'm a Canadian).

-perhaps the presence or absence of hair has some  physical attraction issue. The more mating at a certain time of year means a few more % of women are pregnant and a few more  % of babies are born when certain nutritional or social variable are present  (ok...this one is a stretch).   

There's more to hair than warmth. Those gorillas who lounge around the equator are hairy guys.   

[Geezer]

Seems pretty unlikely, but could it be a body's way of getting more vitamin D?

BTW, there is a theory that our ancestors were successful hunters because they had no hair on their bodies. This allowed them to run for very long periods and simply exhaust the animal they were hunting.

[raptorguy]

Seems pretty unlikely, but could it be a body's way of getting more vitamin D?

BTW, there is a theory that our ancestors were successful hunters because they had no hair on their bodies. This allowed them to run for very long periods and simply exhaust the animal they were hunting.

That's interesting about hair and hunters. In the Canadian north as long as a group of hunters could keep a prey animal in view they could keep pursuing it, eventually catch it and 'do it in'. A wolf can out run a male is the short run but 'poops out' to exhaustion before we do....most aninals also don't recover their energy as quickly as humans.

[4312]

Hair falls out after winter as a result of resource depletion during the winter. We move less, eat less fruits and vegetables, and have less sun. I always take health supplements to prevent hair loss and lethargy. One of my drugs is biotin. I absolutely love this product <<<Spam link removed>>>. After a few weeks, my skin cleared up and I had an amazing natural glow. My hair grew two inches and I felt much healthier.

[scarlettzou]

It is perfectly normal to lose between 25 and 60 hairs a day. In some cases, however, this loss becomes more significant when autumn arrives.