Light therapy is not to be taken lightly — it’s a treatment that has improved the lives of many people.

Patients sit near a special lamp that emits bright light for a certain amount of time every day, thereby affecting their internal clock that regulates things as basic as when they go to sleep and when they get hungry. That clock, known as a circadian rhythm, is influenced by environmental factors like sunlight, and the light box mimics daylight that could be missing during winter in colder climates — one of the drivers of the type of depression called seasonal affective disorder. When the internal clock is off, the production of the sleep hormone melatonin and the mood-altering hormone serotonin could be off too. But there are many misconceptions about light therapy.

idea-1584708_1920 Light therapy boxes emit light much brighter than normal indoor lighting. Photo courtesy of Pixabay, public domain

Myth: Light therapy is only for depressed people

While most prominently used to treat seasonal affective disorder, light therapy has been found to treat other types of depression as well as sleep disorders, jet lag and dementia, according to the Mayo Clinic.

Read: Depressed and Anxious? Check Your Internal Clock

Myth: All light therapy is the same

There are other light therapies that, for instance, treat skin conditions like psoriasis, the clinic says. But that kind of light is different, and could damage your eyes and skin if used to treat mental conditions.

“Most typically, light boxes filter out the ultraviolet rays,” the National Institutes of Health say.

That means tanning beds won’t work because they release UV light, so it’s best to see a medical professional for treatment instead of someone at a beauty salon.

Myth: I’ll be staring into a lightbulb for a few hours

That may be what light therapy sounds like, but patients are not simply sitting around with nothing to do, looking into a bulb. According to Harvard Health Publications, the treatment often lasts about 30 minutes daily, “usually as soon after waking up as possible” and you wouldn’t stare at the light box just as you wouldn’t stare at a solar eclipse — that box is putting out light 100 times brighter than most indoor lighting.

“You need to have your eyes open, but don’t look at the light,” Harvard warns. “Many people use the time to read a newspaper, book, or magazine, or catch up on work.”

Myth: Light is harmless

Just because you can’t feel a medicine going through your veins doesn’t mean there can’t be side effects. In addition to potentially affecting sensitive skin and eyes, the Mayo Clinic says eyestrain, headaches, nausea or irritability may occur, although it is often mild and goes away after a short period. One more serious danger is that light therapy could potentially trigger a manic episode in people with bipolar disorder. “If you have any concerns about how light therapy may be affecting your mood or thoughts, seek help right away.”

Fact: Bright lights affect us in other ways too

In addition to stabilizing our internal clocks and our sleep schedules, light therapy may awaken … something else. Popular Science has reported that “a daily dose of bright light could boost testosterone levels to improve men's sexual desire and satisfaction.” When men who had suffered from a low sex drive received light therapy, they experienced a dramatic increase in testosterone levels and their sexual satisfaction.

See also:

Sunshine Could Treat Schizophrenia and Depression

How to Recognize Seasonal Affective Disorder