Light Therapy: How Light Boxes Work

If you've ever suffered from a minor form of seasonal depression (also known as seasonal affective disorder) or if you just haven't had enough energy for your early morning job, you may have heard something about the benefits of light therapy. You may have heard about light boxes, boxes that you look at that send a set amount of light to your eyes to give you more energy. However, many people accept this technology without really knowing the science behind it; others dismiss it as silliness, again without understanding the basic concepts at hand.

Light boxes, when used correctly, are a great form of light therapy, and can lead to more energy and less depression during the darker winter months. Here's an overview of how they work.

What Is Light Therapy?
Light therapy scientists claim that seasonal depression and a decent amount of the fatigue that many people deal with is caused by a simple lack of light to the eyes.

The pineal gland, located behind the eyes, produces a chemical known as melatonin, the chemical that makes us tired (and may also contribute to disorders such as ADHD). This chemical is primarily produced when no light is hitting the retinas, and is probably an evolutionary response that helped to regulate early humans' sleep cycles.

As we've evolved and become more technically advanced, however, we've built offices and other places of work where we spend 8-10 hours of our days without much light, except for the occasional flickering fluorescent bulb which doesn't provide nearly the amount of light that the sun provides. The sun's light, when measured in units of "lux" (the standard unit of illumination) is somewhere from 50,000-100,000. Your home or office lighting only provides about 200-500 lux.

Pretty big difference, isn't it? With less light, our bodies produce more melatonin, and the negative effects of the chemical, such as seasonal affective disorder, depression, fatigue, and other not-so-great phenomena tend to occur.