Increasingly, light therapy is being employed to reset our body clocks, sometimes in conjunction with melatonin and sometimes as a standalone solution, regardless of the cause of the disruption. Scientists are uncovering that light therapy holds potential for treating various disorders beyond Seasonal Affective Disorder (SAD).
Individuals afflicted with early morning insomnia often struggle to initiate sleep in the early hours of the morning. In a 1993 study conducted in South Australia, nine people with early morning insomnia underwent bright-light stimulation in the evening. They received phototherapy involving exposure to 2,500 lux light from 10 p.m. to midnight. The outcome was significant: they fell asleep at their usual times but stayed asleep for an average of one and a half hours longer than usual.
Enhanced Productivity
An investigation in Wetaskiwin, Alberta, Canada, clearly demonstrated that students in classrooms illuminated with full-spectrum light exhibited lower absenteeism and achieved higher academic performance compared to students in classrooms lit with standard fluorescent lighting.
Delayed sleep phase syndrome (DSPS), or night-owl insomnia, refers to a form of insomnia where individuals struggle to fall asleep until the early morning hours. This condition often leads to alcohol and sleeping pill abuse and typically emerges during the teenage years due to a misaligned biological rhythm that resists conforming to a normal bedtime.
In a study focused on individuals with delayed sleep-phase syndrome, a regimen of bright light exposure for two hours in the morning and avoidance of bright light in the evening led to a successful adjustment of the affected individuals' circadian rhythms. Notably, both sleep duration and morning alertness significantly improved during the treatment.
Jet Lag
Light therapy has proven effective for some people in preventing or mitigating the effects of jet lag. Experts suggest that individuals planning to travel eastward, such as to Europe, may benefit from getting up a few hours earlier than usual on the day of their flight. Engaging in outdoor activities in the sunlight or staying indoors with bright lighting is recommended. Staying awake and surrounding oneself with light can help adjust the internal body clock to align with the new time zone upon arrival.
Late-Shift Drowsiness
According to the National Commission of Sleep Disorders Research, night-shift workers are two to five times more likely to experience drowsiness and accidents on the job. Late-night sleepiness can impair the judgment of professionals like police officers, firefighters, and ambulance drivers. A concerning number of aviation accidents have also occurred during the early hours.
Analysis of ten studies involving night-shift workers revealed that their circadian rhythms could be successfully adjusted through exposure to bright light during the night and complete darkness during the day for four days. These adjustments led to a significant improvement in alertness and cognitive performance during work hours, along with an average of two hours of extended daytime sleep. Recent studies indicate that young subjects' circadian rhythms are more adaptable compared to middle-aged subjects. In one study, exposure to bright light in the morning and the use of protective eyewear when going home from work produced the best performance improvement. Scientists believe morning sun exposure may be influencing the circadian rhythm shift, which can be hindered by wearing eyewear. The optimal effect is achieved with three hours of exposure to bright light, with no additional improvement observed with six hours of 4000-6000 lux light exposure.
Bulimia
Bulimia, an eating disorder characterized by binge eating followed by purging, typically develops in women during their teenage or early adult years. Left untreated, it can lead to serious physical and emotional consequences. Researchers have observed that bulimic episodes tend to occur more frequently in winter, suggesting a potential seasonal component. High-intensity light therapy has shown remarkable improvements in individuals with this condition.
Lupus
Lupus, an autoimmune disease in which the immune system mistakenly targets the body's own tissues, affects a greater number of women than men and manifests with diverse symptoms including fatigue, rashes, joint pain, and kidney damage.
Individuals with lupus are typically advised to avoid sunlight as it can exacerbate their symptoms. However, scientists have found that a specific type of ultraviolet sunlight, UVA - 1, can help alleviate lupus symptoms.
Nonseasonal Depression
Nonseasonal depression affects an estimated 10 to 15 million Americans, leading to approximately 30,000 suicides each year. The success of light therapy in treating SAD has prompted investigations into its effectiveness for nonseasonal depression, with promising initial results.
Prolonged Menstrual Cycles
The standard menstrual cycle lasts about a month, but some women experience cycles twice as long.
In a study, women with prolonged menstrual cycles were instructed to sleep with a 100-watt light on for five nights during the middle of their extended cycles. The results were remarkable; their menstrual cycles shortened. Researchers speculate that the light may influence the regulation of female sex hormones. If confirmed, phototherapy may one day be used to address certain cases of infertility.