Light and Depression

Q:I see ads for home-use high-intensity light therapy box kits to help reduce the winter blues. Our local hospital uses them. Do these high-intensity lights use a lot of electricity and do they really work? - Al F.

A: My neighborhood hospital also has a light therapy room for which they charge a fee to use it for a 30-minute session. The "winter blues" are referred to as Seasonal Affective Disorder (SAD) by physicians.


I am not a doctor, but some doctors suspect that millions of people suffer from SAD-related problems. Some typical reported symptoms are fatigue, craving sweets, weight gain, difficulty waking, irritability, etc. Before attempting any self cures like this, always consult your physician first.

The brightness from SAD light kits is fairly intense to create the desired effect on your body. A brightness level of about 10,000 lux for 15 to 30 minutes is often considered to be the threshold for beneficial results. NEVER use sun tanning or infrared heat lamps for this purpose. Most home-use SAD light kits use efficient fluorescent tubes. To produce 10,000 lux brightness, some models use less than 100 watts.

Even at today's high utility rates, it uses less than a penny's worth of electricity per session. This is much cheaper than using the SAD lights at the hospital.

You do not have to stare at the SAD light box when you use it. Set it on your kitchen table while you have breakfast, read the newspaper, etc. You can often turn off other lights and save overall on your electricity bills.

A brightness of 10,000 lux sounds intense, but it really isn't. At noon on a sunny day, the brightness outdoors is over 90,000 lux. The lux level drops as you move further from the light source, so you should sit fairly close to the light. A kit that provides 10,000 lux at 24 inches is ideal.

There are some other interesting light-related, low-electricity-usage devices designed to minimize SAD. Dawn simulator lights allow you to wake slowly to the rising sun in the winter just like you do in the summer. These lights gradually brighten over 15 to 60 minutes.

There is also a built-in backup audible alarm. Digital models can be programmed with your area's latitude and adjust themselves automatically. Others include natural alarms like the gently increasing sounds of morning birds or a babbling brook. A light visor, with rechargeable batteries, is worn like a sun visor. It produces 2,500 lux and does not interfere with your activities. Although not as bright, realistic lighted window kits can be hung on a wall to cheer up a room. They include changeable scenes - beach, English garden, golf course, etc.