Does melatonin as a supplement really work for better sleep in older age?

As you get older, your body produces less melatonin. The evening peak becomes lower and its timing shifts. That is one of the reasons why many people over 55 have more difficulty falling asleep, wake up more often during the night, or wake up too early.

A small randomised trial in 24 healthy older adults (average age 64) showed that 5 mg of melatonin, taken half an hour before bedtime, noticeably improved sleep efficiency. This worked through longer periods of light sleep and fewer brief awakenings. A low dose of 0.3 mg produced only a trend, with no measurable difference. This was, however, a small two-week study, so the findings are promising but not yet definitive.

In older sleepers, melatonin generally has a more favourable side-effect profile than classic sleep medications such as benzodiazepines, which increase the risk of falls and can affect memory. However, little is known about the long-term use of melatonin in older adults. Melatonin acts on multiple organ systems, and what that means over the long term has not yet been thoroughly investigated.

Its effect on sleep problems and disruptions to the day-night rhythm in older adults is described as modest. Melatonin is not a powerful sleep medication that makes you fall asleep immediately, but it can provide some support for your rhythm. If you also limit evening light exposure (particularly blue screen light), that helps too: blue light in the evening further suppresses the already limited melatonin production of older people.