When we hear the words “light therapy” we probably think of SAD, or Seasonal Affective Disorder. This was in fact the reason I became familiar with light therapy. I am Southwestern gal from Phoenix, Arizona and I moved to Columbus Ohio where cloudy days, rain, and snow were more common than sunshine. I had never experienced issues with sadness or depression until a few years after my move and I think it is directly tied to less activity and less sunshine.
Light therapy is often prescribed for the winter blues, but, as it turns out, it may be useful for much more than that.
What is Light Therapy?
First, let’s take a look at what light therapy is. According to the Mayo Clinic website, light therapy “is a way to treat seasonal affective disorder (SAD) and certain other conditions by exposure to artificial light.” But not just any artificial light. If that was all that was needed, no one would need light therapy because exposure happens merely by going about life. The fluorescent lights at your office are not going to cut it.
Modern light therapy usually involves what is called a light box or happy light. A light box is a device that emits a very bright light of certain wavelength. Frequency and intensity are important to reach a therapeutic level. Intensity is measured in units called lux. For comparison: according to psychoeducation.org: bright moonlight is 1 lux, a candle is 10-15 lux, office lighting is 300-500 lux, etc. The scale increases up to bright sunlight, which is 20,000-100,000 lux. There seems to be a consensus among various studies that therapeutic levels are 10,000 lux for 20-30 minutes.
Health Benefits of Light Therapy
When used to alleviate symptoms of seasonal affective disorder and circadian rhythm disorders, it seems to work on receptors located in the retina of the eye. When using a light box the device must be positioned so the light hits the receptors at the bottom of the retina. These receptors are what communicate to the brain that it needs to prepare the body for the activities of the day.
As it gets dark earlier in the evenings AND because you never really had enough light exposure during the daytime hours you might begin to feel down. A natural reaction to feeling down is to withdraw, and withdrawal usually brings less activity, heavier eating, feeling sluggish, feeling fatigued; that leads to even less exposure to light, which affects not only the hormones such as melatonin that regulate sleep, but also the body’s ability to manufacture vitamin D on its own. A vitamin D deficiency then causes more fatigue, and directly impacts your happiness and mental well being.
Who Should Consider It?
As stated earlier, light therapy (also sometimes called phototherapy or bright light therapy) is most often associated with seasonal affective disorder and other forms of major depression. If you suffer from these then ask your doctor about light therapy, or take the initiative and order a light box to see how you feel.
Light therapy may also be used in instances when an alternative to antidepressants is needed (pregnancy), or a patient needs to be on a lower dose of antidepressants. For instance, a patient who is not tolerating antidepressants well or who is having liver or kidney issues might need to go on a lower dose of antidepressant, and light therapy may facilitate that. Light therapy can also be great for those that absolutely do not want to go the pharma route.
There are also a variety of circadian rhythm disorders in which light therapy may be useful as treatment, either alone or in conjunction with other therapies. Circadian rhythm disorder is an umbrella term for sleep disorders that stem from a disrupted internal body clock. What should happen is that as morning comes, our body temperature and blood pressure rise and melatonin levels decrease, which is what helps us wake up and start the day. If our biological clock, is disrupted or offset, this either does not happen at normal levels or does not happen at acceptable times. This ultimately means they have trouble waking with energy and falling asleep when it is time to.
Jet lag also falls within the realm of circadian rhythm sleep disorders, although this is one that is usually temporary and easily fixed. This would be a more serious problem in people who travel frequently in and out of different time zones, and in cases like this light therapy would likely be useful.
There is actually a pretty nifty product for those folks. It is a light therapy alarm clock that, beginning about an hour before a person is set to wake up, gradually increases the light in the room as it nears time to awaken. This is supposed to trick your brain and make you think the sun is rising and it is time to get up.
The key with light therapy is consistency. No therapy, whether natural or pharmaceutical in nature, is going to work well without an effort to be consistent. Light therapy should ideally be done every day in order to get the most benefit from it. Though once you start to see the benefits it will become and enjoyable part of your day.
