WASHINGTON – It’s the middle of winter. It’s been cold. It gets dark early. It takes a toll on many people.
Lots of folks get depressed when dealing with cold, gray winter days, but one lighting expert has found a way to fight back: Your winter blues could be caused by blue light.
Dr. Richard Hansler, director of the Lighting Innovations Institute at John Carroll University and author of three books on the effect of light on human health, says that blue light is part of white light, and it’s the part that keeps you going. So there’s a time for blue light, and a time to go without it.
Humans evolved near the equator, with 12 hours of light and 12 hours of darkness. Body clocks are reset in the morning by exposure to light, and 12 hours later, people start making the sleep hormone melatonin.
“It’s important to get lots of light in the morning, especially blue light,” Hansler says.
Otherwise, you start making melatonin far too early, and you feel sluggish and depressed all day.
In the evening, it’s important to avoid blue light as much as possible — it’s melatonin time, and people don’t need their bodies getting revved up.
“The amount of blue light we get due to artificial lighting actually keeps our bodies from making melatonin,” Hansler says.
And falling asleep with the lights on makes things worse. Not only do you make less melatonin, but “it also resets your clock to a later time, which makes your body confused. It’s like being in continuous jet lag,” he says.
Avoiding blue light for a few hours before bedtime helps you make melatonin, which helps you sleep better.
And Hansler’s group has developed light bulbs that don’t produce blue light, and glasses that filter it out. You can find them on Low Blue Lights.