?When we're exposed to high intensity light, our body temperature increases, and melatonin levels rapidly decrease.



?Exposure to natural sunlight also delays the temperature drop. This allows you to stay awake and alert for longer periods of time.

?Lack of sunlight results in higher melatonin levels, this leads to lower body temperature levels, feeling very sleepy, and tired through out the day.

Lack of sunlight will create a flat-line effect in your body temperature, because it will not get a chance to rise high enough, your body temperature won't fall low enough during the night either. If your body temperature is flat-lined, this could cause major sleeping problems, and it will be very difficult for you to sleep deeply for long periods of time. A lot of people who complain about ?poor sleep? usually don't get enough sunlight.

Consider how for the most part of our evolution we were always outside during the day, it seemed that nature intended us to be this way, then suddenly over the past 100 years we drastically changed our exposure to natural sunlight. Most of us hardly get any sun today at all! We drive to work in a car, we wear sunglasses, we work in offices, what kind of effect do you think this has on our sleep clock?

How much Sunshine is Enough?

This is probably the most important factor discussed in this whole book and the concept of sleep therapy. The amount of sunlight that enters your eyes has a great impact on your sleep rhythm.

*Exposure to high intensity light increases our body temperature. Rise in our body temperature decreases out melatonin levels.

*When exposed to natural sunlight, our body delays the temperature drop, thus allowing us to be awake and aware for longer times.

*Lack of enough natural sunlight results in more melatonin level leading to lower temperature levels, sleepiness and tiredness.

Not going out in the sun creates a flat line effect on our body temperature rhythms. Our body temperature will not rise high enough during the day and as a result will not fall enough during the night. This will result in sleep problems and you will be deprived of deep sleep most of the time. Most of us who complain of lack of sleep simply do not get enough sunlight.

Going back in time, man has always been an outdoor animal, out in the sunlight all through the day and sheltered at night only because of the cold. This continued for so many million years and suddenly we are looking at changing sleeping habits and avoiding sunlight by cars, sunglasses, sheltered offices in the past 100 years. Is it so easy to change a million year legacy in 100 years. Your sleep clock will not change so fast.