LongevityReducing winter blues and improving sleep quality

Fatigue, exhaustion, listlessness, loss of appetite and weight gain are typical signs of the winter blues, also known as seasonal affective disorder (SAD). The use of red light and near-infrared light can be an effective solution to combat the winter blues and sleep disorders.

Under the influence of light, our bodies produce serotonin, the ‘happiness hormone’, and in darkness, melatonin, the ‘sleep hormone’, which controls our sleep-wake cycle. During the dark winter months, this cycle often becomes unbalanced.

The use of light can restore the natural sleep-wake cycle and reduce the winter blues. A study compared the effectiveness of very bright white light (= bright light therapy, BLT) and barely visible near-infrared light (NIR). It showed that there were no significant differences between bright white light and near-infrared light.

Most people are exposed to a lot of artificial light, which disrupts the circadian rhythm, i.e. the normal 24-hour rhythm. Blue light from smartphones and screens in the evening can have a particularly negative impact on sleep quality, as it interferes with the production of the sleep hormone melatonin.

The use of red light can help regulate the body's natural chronobiological functions and increase the production of melatonin, which promotes sleep and regeneration. The light can also be used to restore the biorhythm in cases of jet lag.

A study involving female athletes showed that after just 14 days of regular use in the form of a 30-minute full-body irradiation in the evening, sleep quality improved significantly. At the same time, melatonin levels in the blood serum increased and endurance performance improved significantly.

Current research findings also highlight the positive effects of red light exposure on the so-called glymphatic system in the human brain. This newly discovered waste collection system removes waste products from the brain. Stimulating this system promotes the regenerative efficiency of sleep.