Humans are classified as diurnal creatures—we are predisposed to sleep at night and awaken during the daylight. In recent years science has begun to uncover the true role of daylight and darkness in our sleep cycles, however. Our circadian rhythms—the biological timer that tracks our sleep and waking hours—will continue to operate on a natural day and night cycle even if we try to change our schedules. Thus, someone working a night shift may still naturally feel sleepy when night falls. Likewise, jet lag occurs when the brain’s biological urge to remain active in the sunlight conflicts with the number of hours the traveler has been awake after crossing time zones. Certain colors of light, however, can inhibit the brain’s release of melatonin and alter the body’s natural sleep cycle.

“Light works as if it’s a drug, except it’s not a drug at all,” George Brainard, a neurologist at Thomas Jefferson University in Philadelphia and an early researcher of light’s effects on the body’s hormones and circadian rhythm, told the New York Times.

The Retimer is one of many products marketed toward light-aided circadian rhythm adjustment. The product—light-emitting spectacles—can help the wearer reduce jet lag, increase energy, as well as overcome sleepiness and fatigue simply by shining green wavelengths of light into the eyes. The light is shined from below so the wearer can look ahead without being blinded. The green light triggers the brain to release less melatonin, automatically adjusting its biorhythms.

The Retimer was developed after 25 years of research, and its Web site even offers a “Jet Lag Calculator” to advise the proper times to wear the glasses for best results. Simply enter departure and arrival place and time details, and the program will help the Retimer reset your biological clock faster than any amount of coffee or Red Bull could. The product is also recommended for shift workers. It is currently available for $260.

[Image via Re-Timer]