Melatonin, the sleep hormone

This page is for answering all the questions you have about melatonin. The information is supplied in two separate parts, to facilitate access.
Melatonin, its use and benefits
Questions about possible risks
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What part does melatonin play ?

Nowadays, trouble in sleeping is a very common malady for many individuals. Although our bodies make melatonin by means of the pineal gland (situated behind the brain) during the night (peak secretion is between 2 am and 3 am), all too often it is desperately lacking. The system uses it as a regulator of the circadian rhythm (sleep rhythm).
The production of melatonin is at its maximum in adolescence and diminishes with age. It is the biological clock’s regulator. Melatonin acts at night: it is the principal source of drowsiness, causes yawning and the desire to sleep and improves the quality of sleep. It relieves tension and stress, brings a feeling of relaxation and tranquillity. It is particularly effective for those who are sensitive to jetlag, for insomnia and the improvement of worker's lives.
Melatonin further acts on fluidising of the blood and arterial pressure. Finally, it neutralises free radicals and thus limits the body’s aging process. It is an excellent skin regenerator and a defence of the immune system. What’s more, being a major antioxidant, those following cancer treatment with gamma rays or chemotherapy can usefully have recourse to it, to aid more rapid recovery of the immune system.

How do you detect melatonin deficiency?

Most of the symptoms are linked to sleep: glassy eyes, tired manner, restless sleep, difficulty falling asleep, difficulty in getting up, a feeling of not being rested, the feeling of not wanting to go to bed, poor resistance to jetlag... It is equally possible that you will be irritable, worried, anxious, aggressive or tense.

How do you remedy melatonin deficiency?

It is certainly possible to bring together all the conditions ideal for falling asleep: to have an agreeable ambient temperature (between 18 and 25° C), to prioritise a full night’s sleep, to prefer food rich in melatonin (rice, maize, oats, bananas,...), to round out your food with calcium or magnesium just before going to bed, to limit coffee and alcohol. But despite all these precautions, a medical opinion may prove indispensable.
Think about having your blood melatonin level tested (an acceptable level fluctuates between 15 and 35 pg/ml in the day and is over 100 pg/ml at night). Depending on the results, the doctor will prescribe you a dose varying from 0.5 to 10 mg per day one hour before going to bed. A commonly reasonable dose is 3 mg per day.

What contra-indications are there for melatonin supplementation?

Taking melatonin is not advised before flying, for pregnant or breastfeeding women, for children or for people with mental problems. It is also not advised in cases of lymphoma, leukaemia and ovarian cancer. If too large a dose is taken, there will be a feeling of drowsiness and lethargy on waking.