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The POWER of Light!

The days are getting pretty short, especially here in the northwest. In the winter, Anchorage loses about 14 hours of sunlight, Seattle loses about 8 hours and Arizona loses only 4 hours. Countries like Ecuador and Columbia on the equator don't lose any sunlight in the winter. Up here in the Pacific Northwest we definitely notice the shorter and darker winter days.

Is Less Sunlight Harmful?

The answer seems to be yes. Including even southern states like Arizona and Texas that don't lose much sunlight, almost half of Americans state their "mood declines" during the winter and 1 out of 4 report some amount of depression in the winter months. The numbers are much higher if you limit your survey to northern states like Washington or Alaska.

Medical visits for treatment of depression spike in the winter and many people are diagnosed with Seasonal Affective Disorder, abbreviated as SAD and also known as Winter Depression. SAD is generally considered to be depression caused by inadequate light exposure due to the darker winter days. To learn more about SAD go here.

Bright Light is at Least Part of the Cure!

Light treatment is a very well documented and successful treatment for SAD. For this treatment the patient sits in front of a SAD light for 30 minutes each morning. A quality SAD light will deliver about 10,000 LUX of light. To put that in context, most indoor houses have about 100 LUX of light intensity. An overcast day outside is about 1,000 LUX and a sunny day is anywhere from 10,000 to 100,000 LUX. Hence, a quality SAD light that delivers about 10,000 LUX is equivalent to a less bright sunny day.

The ongoing question about SAD has always been: Is it best to use the SAD light in doors? Or go outside, where they might be exposed to far more light on some days and less on other days? Part of the answer has to do with your desire to use other effective treatments for depression such as exercise. Compared to sitting in front of a 10,000 LUX SAD light, if you went outside on an overcast day for a 30 minute walk, you might get less benefit from the lower amount of light, but you would get the additional benefit of exercise which is proven to be more effective than antidepressant drugs. In all probability, the added benefit of the walk would more than compensate for the lower light on an overcast day. And without a doubt, on a sunny day, going outside for a 30 minute walk would beat sitting in front of the SAD light. However, if going outside is not an option for you, the SAD light would be a great investment.

And don't forget the other treatments for depression including supplementing Omega 3s, shown to reduce depression by 64% to 71% in a study published last year.

Bright Light at Night is Harmful

Interestingly, bright light is not always good. Timing is important too. Recently scientists tested the effects of bright and dim light on peoples metabolism (Diabetologia 65, 721–732 (2022)). The natural pattern is for bright light during the day, followed by dim light in the evening and no light during the sleeping hours. When we break this pattern, it appears that bright light in the evening and at night tends to disrupt your natural circadian rhythm and causes damage to your metabolism.

Under very tightly controlled circumstances, researchers tested the metabolic effects when people were exposed to 10 hours of bright day time light followed by 5 hours of dim light in the evening vs others that were exposed to the opposite: 10 hours of dim light during the day and 5 hours of bright evening light.

Those that had the bright DAYTIME light had more rapid metabolism at night and decreased insulin resistance. This means they burned more calories, were less prone to weight gain and more resistant to developing diabetes.

This is too much light for evening time.

Those that had the bright EVENING light, had slower metabolic rates, and increased insulin resistance. Thus they were more prone to obesity and diabetes. They also had lower amounts of melatonin, and hence did not sleep as well.

Since 40% of adults in America have obesity and another 1/3 are overweight, almost everybody should be interested in burning more calories and decreasing insulin resistance. When you throw in the potential sleep improvements, everybody should be signing up for bright day time lights and dim evening lights!

Artificial Out Door Light at NIGHT is Harmful

Scientists have also found that artificial outdoor lighting at night increases the incidence of diabetes in entire neighborhoods.

This study that involved more than 98,600 people found detrimental effects to those exposed to high levels of artificial out door light. The study, published in the journal Diabetologia used satellite data which measures artificial light levels excluding the sun and moon.

The group most exposed to light pollution at night had a 28% higher rate of diabetes than the group which was least exposed. The lead researcher said:

'Our findings contribute to the growing evidence that light at night is detrimental to health, and point to outdoor light at night as a potential novel risk factor for diabetes.'

The intensity of night light for the 20 per cent of people with the highest light exposure was 69 times greater than those with the lowest light exposure

Colored Light is Therapeutic

Red Light Reverses Skin Aging

Dermatologists are using non thermal red light to improve complexion and reverse skin aging. According to a prospective, randomized, and controlled study of 136 people, red light reduces fine lines, wrinkles, and skin roughness, and increased intradermal collagen density. The treated subjects experienced significantly improved skin complexion and skin feeling. The improvement in skin roughness was confirmed objectively with profilometer readings and increased collagen density was confirmed with ultrasonography. A blinded clinical evaluation of photographs confirmed significant improvement in the treatment group compared with those that weren't treated. (Photomed Laser Surg. 2014 Feb;32(2):93-100.)

Green Light Reduces Migraines

New research from the University of Arizona Health Sciences found that people who suffer from chronic migraines may benefit from green light therapy, which was shown to reduce the frequency and intensity of headaches and improve patient quality of life.

Overall, green light exposure reduced the number of headache days per month by an average of 60% after just 10 weeks, compared to no change after the white light placebo treatment. (Cephalalgia. 2021 Feb;41(2):135-147.)

A 60% reduction in chronic migraines is phenomenal and compares very well with other treatments. For example, Botox, which is very expensive, after 25 weeks of treatment only reduced headache days by 12% more than the placebo treatment. (Headache. 2010 Jun;50(6):921-36.) Topiramate, another drug approved by the FDA to prevent migraines, after 13 weeks only reduced headache days by 11% more than placebo. (Headache. 2007 Feb;47(2):170-80.)

UV Light Treats Psoriasis and Eczema

Ultraviolet light is part of natural sunlight and is therapeutic to a number of persistent skin problems. Ultraviolet therapy is referred to as UV phototherapy. Skin conditions that can be treated with UV phototherapy include psoriasis and eczema.

Psoriasis and eczema are often treated with steroid creams. Unfortunately, steroids, even used topically can have serious side effects. Safer drugs such as Dupixent that you have probably seen advertised on TV, are available, but are very expensive. (for example Dupixent costs $59,000 a year)

Psoriasis treated with UV phototherapy

Recently, the American Academy of Dermatology published a statement entitled a

"A call for action!"

In this Call for Action they state that UV phototherapy not only has the longest track record but is also one of the most cost effective and efficacious treatments for psoriasis and eczema available and should remain a consideration for patient treatment. (J Am Acad Dermatol. 2015 Jun;72(6):1078-80.)

I used full body UV phototherapy in my own practice and treated many cases of psoriasis and eczema, and other conditions, many of which had failed multiple other treatments. In my experience, phototherapy is a reliable, effective treatment and much less expensive than many other treatment options.

What Should I do Now With This Information?

Here are some basic steps everybody should implement.

Start by being aware of the effects and benefits of light in your life. Reading this article is a good start, but this article just begins to scratch the surface of what light can do. Keep your eyes open and you will see lots more information about light from many different sources in the future. Stay informed!

Make it a point to get more sunlight everyday, by being outside, summer and winter. Go for a daily walk, take care of a garden, and find out door hobbies. Sunlight has more benefits than risks.

Have bright lights in each room. Turn them on first thing every day. Open your curtains wide, early in the morning. Let as much sunlight in as possible.

Each room should also have softer, dim lights to use in the evening. At dinner time, or around 5-6 PM, turn off the bright lights and use only the dim lights and small lamps all evening long. All screens should probably go off 30 minutes before bedtime.

Close the curtains at night to block all outdoor light. Try to sleep in as dark a room as possible.

The above steps will reinforce your natural circadian rhythm and do much to strengthen your general health, in addition to some of the specific benefits listed in this article.

If you have insomnia, ask yourself a question. Am I using light to reinforce my circadian rhythm and promote sleep? Or am I misusing light and contributing to my own problem?

If you experience depression any time of the year, consider light as part of the solution.

Do you have treatment resistant migraines? Consider adding green light to your regimen.

If you have psoriasis or eczema, phototherapy administered or prescribed by a knowledgeable dermatologist, or other health care provider, might very well be your best treatment.

Take care and BE HEALTHY!

CW Jasper

November 2022

© 2022· Content is Property Created by CW Jasper


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Gerald Hacker
Gerald Hacker
29 de nov. de 2022

I am curious as to what role if anything does vitamin D3 play in sunlight and its impact both with and without sunlight exposure.


I found this article very interesting... and while some items were well known, others came as a surprise. I'm about to look around for green light-emitting products so I can make recommendations to patients with intractable migraines... do you have any recommendations for specific sources? What wavelength range is most effective?

Doctor Jasper
Doctor Jasper
28 de nov. de 2022
Respondendo a

Go to the study referenced above and when you get there, go to the free full text link. In the full article you will find the name of the supplier and the model number of the green lights. They used 6 foot long LED strips. I believe these are the same green lights they used in a fibromyalgia study that also had impressive results. With green lights the fibromyalgia pain reduced by over 40%. I'm thinking about getting the green lights for my little spa.


Dale Hawkins
Dale Hawkins
24 de nov. de 2022

What is your opinion on using a tanning bed in the winter for exposure to UVA and B light?

Doctor Jasper
Doctor Jasper
25 de nov. de 2022
Respondendo a

Maybe for plan B or plan C. Here are the problems. Can you trust the quality of the lights you get for home use? What proportion of the light is UVA, UVB and UVC? And whatever the label says, can you trust it? And if you go outside and walk you get the added benefit of exercise. And another issue, is this: we have some evidence there are some other parts of the light or energy spectrum we are exposed to outside, that haven't been identified yet. We don't know how essential this unidentified thing is yet, but to me, I don't want to risk not going outside daily.


Dale Hawkins
Dale Hawkins
24 de nov. de 2022

Great article Cary. I have followed most of these recommendations for many years with very good benefit.

Many years ago when I was doing shift work I suffered for about a year from severe insomnia and the two things that really improved my sleep was wearing a blindfold at night and ear plugs.

It is very difficult to completely black out a room for sleeping. o much easier just to put on a blindfold.

Doctor Jasper
Doctor Jasper
24 de nov. de 2022
Respondendo a

I've never used a blindfold at night, but have heard good reports about it. We have made some effort to get our bedroom blacked out, and we did pretty good. My wife got the ladder and climbed up and covered the inside of our skylight, to block out moon light etc, and that made a big difference. I ordered the black out blinds and installed them on each window. Huge difference. Then we covered up all the little lights on all our devices, etc. Our bedroom is pretty dark now. I never wanted to try the blindfold because I thought it would be irritating, but I've heard the cloth ones are pretty easy to get used to. I might think…

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