Melatonin has become one of the most frequently taken supplements in the US over recent decades, particularly among older individuals. Unfortunately, no general agreement exists on an optimal dosage or effect on sleep quality for this supplement and study results vary considerably between studies on older individuals using it.
Researchers conducted a study involving 24 healthy, older individuals to investigate whether sleep could be improved using either high-dose or low-dose melatonin supplements. Their researchers discovered that higher dose had an impressive impact, increasing total sleep time compared to placebo by over 15 minutes for nighttime sleeping and 30 minutes for daytime restful slumber.
Researchers found that sleep deficiency increases with age, with many older individuals reporting taking melatonin due to the many disadvantages of traditional prescription sleep aids; yet little evidence on its effects on their health was available at that time. This study provides insight and evidence that shows how timing and dosage must be considered when considering supplements such as melatonin for older individuals.
Melatonin, an endogenous hormone produced naturally by our bodies, plays an integral part in helping regulate day and night sleep-wake cycles. Melatonin levels tend to peak around bedtime; however, older individuals often produce lower amounts. Exogenous melatonin supplements are readily available without a valid prescription and can typically be taken before bedtime as a dietary supplement capsule or pill.
Researchers conducted a comprehensive examination of the effects of melatonin supplements by recruiting healthy older individuals without history of major sleep issues – 24 participants between 55-78 who were all screened for sleep disorders as part of this study.
Participants of this study lived in separate rooms without clocks, windows, or other time indicators during the 1-month study period. These researchers used a forced desynchrony protocol, using 20-hour cycle schedules rather than 24-hour days and nights to break free from the circadian clock’s rest-activity effects. Sleep was now possible to schedule both nightly and daytime with similar wakeup duration before sleeping each time. Randomly assigned participants received either a placebo pill for two weeks and then either low dose 0.3 mg melatonin or high dose 5 mg half an hour prior to bedtime, with polysomnography utilized to record muscle tone, eye movement, brain waves and other key sleep metrics.
Research showed that low doses of melatonin did not result in statistically significant changes to overall sleep time; rather, any differences were only evident when biological day sleep was scheduled. Individuals taking 5 mg dose increased both total sleep time and efficiency significantly whether sleeping was scheduled during day or night time.
Researchers noted that larger trials with other melatonin dosages would need to be conducted in order to ascertain if doses between 0.3 and 5mg could also work effectively, since individuals who suffered from significant sleep disorders were not included in this research, so its results may not apply equally well.
