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The Effect of Photoperiod on Humans, Keratosis Pilaris, & Cholinergic Urticaria

March 22, 2009 by Hivesguy

As always, I am thinking of potential theories of what causes cholinergic urticaria. As most of you know who read the blog & forum regularly, I am hoping sunlight exposure has something to do with it. So IF sunlight does have some involvement, I ask myself, “How does it effect us, and how could it cause Cholinergic Urticaria?” At this point, I still really think sunlight exposure is a HUGE factor.

Again, I base this on the fact that in a survey on sun exposure, the majority that have taken, so far 78 (and counting) say they get very little exposure. Also, my own experience in the past has shown that periods where I was exposed to lots of outdoors time, I had NO hives. When I stayed mostly indoors, my hives came back. Plus most medical articles suggest cholinergic urticaria often presents itself or gets worse during winter.

On top of that, you may remember my post on discovering that many of us have “Keratosis Pilaris,” which is an overgrowth of a skin protein (Keratin) that results in “bumpy skin.” Not only that, but many website articles indicate sunlight helps Keratosis Pilaris as well.

So after doing some research, I thought I would share some interesting things that could possibly be connected here, and explain WHY this is happening (if it is indeed the cause).

The Photoperiod Effect of Humans, Plants, and Animals

Have you ever noticed how bears hibernate in the winter? Or that dogs seem to lose fur during the summer? Or how about leaves dropping from trees?

You may be saying, “Okay, so what? Whats the big deal?” The truth is, the same thing is responsible for all of these events, the “Photoperiod Effect.” What is a photoperiod? Photoperiodicity is the physiological reaction of organisms to the length of day or night. It occurs in plants and animals. Not only is the period of light important (ie how many hours), but also the changes in the intensity of the light is also important.

The interesting thing is that the seasonal changes that occur as the Earth continues it cycle around the sun (and shifts on it’s axis) is the cause of the photoperiod and has drastic effects on humans, plants, and animals.

For example, a bear knows to hibernate not because of the cold weather, but because of the photoperiod change in which the bear’s pineal gland is sensitive to. Leaves fall due to the same change in photoperiod, and dogs grow more fur during a shorter photoperiod.

In fact, did you know that in your eyes, you have small light-sensitive cells that function to detect the light and transmit it to your glands in your brain? So merely being outside will cause your brain to get signals in hormone producing glands (such as the pineal gland, etc.).

What Kinds of Things Does the Photoperiod Control?

Photoperiod can cause the following changes in animals/plants:

  • It regulates mating & reproduction in animals/plants
  • Causes animals to hibernate, migrate, etc.
  • It causes changes in fur/hair thickness, fur color, etc.
  • It is known to help control, prevent certain diseases

I found various interesting scientific studies & articles related to the photoperiod effect online. One website discussed the health benefits of  being exposed to full spectrum sunlight. It discussed several interesting examples of how photoperiod/sunlight can affect cancer, fish eggs, etc. (Update: I did link to the articles but the links were no longer active).

Another interesting article talks about various health related topics in relation to the photoperiod. It specifically mentions the effect that light exposure has on producing hormones & chemicals such as melatonin.

Another article here discussed an experiment with rats & exposure to light. It seems that photoperiod exposure can also lead to changes in the effectiveness of organ protein levels.

An article here discussed how dogs experiencing seasonal alopecia (hairloss) was actually due to Follicular Keratosis which happened during a reduced photoperiod (people keep their pets indoors too much during winter). What do they recommend doing to treat the animal’s hairloss? Let it get outdoors more to produce more hormones & chemicals via sunlight/photoperiod exposure.

Sunlight Exposure, Photoperiod Effect, Cholinergic Urticaria, & Kertatosis Pilaris:

Okay, so let me tie this all together now. Hair is a form of keratin. Keratin is a protein found in the skin. We all have it, and there are many different “types” of keratin. Hair, nails, and skin cells are all different types of keratin.

In Keratosis Pilaris (something many Cholinergic Urticaria people seem to have), one of the keratin proteins are being over-produced by the body. This blocks skin follicules, and produces hard “plugs.”

Sunlight exposure (Photoperiod) is shown to affect keratin (hair) production in animals (it can increase and decrease it). Just like a dog can shed more hair or grow more hair. Keratin in the skin is just another type of Keratin (just like hair/fur is but 1 type).

When the body is exposed to sunlight, it signals various glands to release and regulate many vital hormones to the body. One person on the forum has found that they sometimes have hyperthyroid issues (hormonal). These hormones affect genes by telling them to “switch on” or “switch off.” This is why suddenly a dog’s hair gets thicker when it gets colder and the photoperiod is shortened.

This build-up of excess skin keratin/cells blocks our sweat glands. It causes Keratosis Pilaris, and for many, also cholinergic urticaria symptoms. The majority of the sweat pores are simply blocked by excessive tissue growth. Again, this is all due to our hormones and sunlight exposure being “out of whack.”

Therefore, when our body goes to release sweat, most pores are blocked. This results in a “stinging” sensation, and also causes us to itch. If we can “suffer” through the torture, sometimes the sweat can find its way out. That happens on really hot days, and if we really get hot. However, if our bodies continue to produce keratin, it will continue to block the pores.

How Am I Going to Do This Sun Exposure Thing?

We must be very careful when going outside for several reasons. I will make a larger post about this in a day or two. But we can overheat and die since we can’t sweat good. We can also risk skin cancer, sunburn, and other dangerous things.

What I have been doing is going out during the less intense sun periods of the day (usually between 2:30-6:00 pm). I try to get about 30 minutes-1 1/2 hours of natural light exposure. I sometimes take off my shirt for a few minutes to get a few more rays.

Again, I am very careful about this to avoid sunburn, etc. It is not yet hot enough to cause a sunburn at this time of year.

Since the eyes play an important role in absorbing light and regulating hormones, I remove my sunglasses for a least 15-30 minutes (again, don’t look at the sun or anything).

The idea & hope is that over time (IF this theory is true), something in my hormones will correct itself. My pores will open up, and cholinergic urticaria will go away. I estimate I should know for sure by mid summer if this works at all or not.

Conclusion:

Everything I said above could be completely WRONG! But I hope I am right. I hope that we can figure out what is causing this.

Even if sunlight exposure & photoperiod have nothing at all to do with Keratosis Pilaris or Cholinergic Urticaria, I still think it is interesting how it can affect our health. However, based on many articles, my own sunlight exposure history, and more, I think there is a link in all of this.

Just something to think about! Hopefully I will have the answer if this is true or not in the next 2-3 months.

Have any thoughts? Feel free to open a thread on the forum and discuss this.

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