Melatonin

Melatonin

Melatonin is a hormone that our body produces itself, and which helps to regulate sleep and our circadian rhythm. Over-the-counter melatonin can be bought at the pharmacy to improve sleep or reduce jet lag.

What is melatonin?

Melatonin (N-acetyl-5-methoxytryptamine) is a hormone that is formed in a gland called the corpus pineale in the brain, from the amino acid tryptophan. Secretion of melatonin from the gland is highest at night and lowest during the day. This secretion is controlled by the amount of light reaching the eye. The hormone makes us sleepy and falls asleep more easily.

The secretion of melatonin varies throughout life. The secretion starts when you are between 3-4 months old, and is highest when you are between 1-3 years old. The secretion then decreases slightly, and it remains at a steady level until early adulthood. As you get older, the secretion will gradually decrease.

Circadian rhythm

Humans have an internal, biological clock that controls several processes in the body in a circadian cycle. This is often called the circadian rhythm or circadian rhythm. This cycle lasts approx. 24-25 hours, but the duration is also affected by external factors such as light, via melatonin. But even if you are in complete darkness for a few days, the body will maintain this circadian rhythm, so you know that there are also internal factors that control it. The circadian rhythm helps control processes such as sleep and wakefulness, body temperature, digestion and cortisol levels.

What affects melatonin levels?

Use of artificial light in the evenings, such as laptop, mobile and TV screens, can reduce the secretion of melatonin and therefore negatively affect the circadian rhythm. This can make it harder to fall asleep. Some medications can also affect our own secretion of melatonin. This applies, among other things, to the group of blood pressure medicines called beta blockers, and the secretion of melatonin is also affected by caffeine and alcohol.

Melatonin secretion is generally highest in autumn and winter, with long and dark nights. In summer and spring, the secretion is lower, as bright light causes a sharp reduction in melatonin. The increased secretion in winter can make us feel tired and lethargic. For this reason, it has been suggested that melatonin, along with serotonin, plays a role in seasonal conditions, such as winter depression. Serotonin is a neurotransmitter linked to depression, which is also affected by daylight and darkness. Current recommended treatment for winter depression therefore includes seeking out daylight or receiving light therapy.

Melatonin used as medicine

Melatonin has been proposed as a treatment for several different disorders, including jet lag, delayed sleep phase syndrome, sleep problems in shift workers, and several other forms of sleep disorders and insomnia. The documentation is variable and incomplete for several of the conditions. The best documented is melatonin's effect against jet lag.

Melatonin for sleep problems

Before trying drugs or dietary supplements for sleep problems, you should try sleep hygiene advice. This can help regulate your own circadian rhythm, and therefore provide a better sleep pattern. You should ensure that you get sufficient amounts of daylight every day, preferably at least 30 minutes, and avoid artificial light from screens in the evenings. Lying down in a dark and cool room can also help.

Other good advice for good sleep hygiene is:

• Go to bed and get up at the same time every day, also at weekends.

• Avoid sleeping during the day (at least no more than 20 minutes).

• Do not consume caffeine or alcohol close to bedtime.

• Regular physical activity, but not right before bedtime.

• Don't be hungry or full when you go to bed.

• Learn a relaxation technique for falling asleep.

• Try to resolve any worries during the day, or write them down on the edge of your bed so you can deal with them the next day.