While the supplement may be taken to help treat sleep problems, it’s not a cure for insomnia; it can help induce sleep, but it won’t help you stay asleep. Melatonin can be effective for conditions such as jet lag, seasonal affective disorder (SAD), and controlling sleep patterns for people who work night shifts.
If you respond well to the supplement, there’s no reason you can’t continue to take it long-term without any negative side effects, but relying on it too heavily could have a negative effect. “It can de-sensitise your receptors so they’re no longer responsive to lower doses of melatonin,” says sleep specialist, Dr Andrew Westwood. “Then, if you come off [the supplement], you might have difficulty sleeping – and require more and more [of it] to fall asleep.”