MELATONIN

17
0

NEW PARMA – october/november 2008

On the eve of summer holidays, some of you who are about to take a trip overseas may think of using melatonin to mitigate the effects of Jet Lag. In fact, probably it is this extraordinary substance’s specific use.

But what is melatonin, first of all? Melatonin is a hormone produced by the pineal gland or hypophysis, which is located in the back of the brain.  From the clinical point of view, it derives from an amino-acid, tryptophane, which is then transformed into serotonin and this, in turn, is turned into melatonin.

The main biological function of melatonin is that of marking the rhythm of our biological clock and acting as an orchestra director for the body’s most important hormones.

Melatonin is produced primarily during the night, when its levels are 10 times higher than during the day, reaching its pick at around 2 a.m. Thus, one may state that the production of this hormone, stimulated by darkness, is a signal for our body that it is time to sleep. Indeed, melatonin has been used for decades to treat sleep-related disorders. In the morning, when we perceive the sunlight’s arrival, the secretion of melatonin stops and other hormones step in, such as the suprarenal ones (cortisol and adrenalin), that help us to get moving.

After the ages of 30-40, the production of melatonin decreases and in our 60s it is approximately half of that of a 20-year-old. This could be one of the reasons why elderly people tend to sleep less.

The action of melatonin is not limited to just inducing sleep, but it acts at other levels too. It is one of the most powerful antioxidants of our body since it fights free radicals, which are the chemical substances that cause damage to DNA, cell membranes and body proteins. These damaged areas are the basis of several diseases linked to ageing, including atherosclerosis, cancer, skin wrinkles and hair thinning.

One of melatonin’s fundamental characteristics is that of being able to succeed in passing the haemato-encephalic barrier thereby exercising its protective action on brain structures and preventing some neurological degenerative diseases, such as Alzheimer’s and Parkinson’s.

Another important action of melatonin is that of strengthening the immune system both by stimulating the thymus to produce more T lymphocytes, and by limiting the production of cortisol, the stress hormone having an immunosuppressive power.  Its hormone regulating action is not limited to just this: in fact, melatonin stimulates the production of GH, i.e. the somatotropic hormone, an anti-ageing hormone that maintains muscle mass and assists in the loss of body fat. Furthermore, melatonin governs the production of the thyroid stimulating hormone (TSH), that makes thyroid synthesize other hormones such as T3 and T4.

It also influences the production of sex hormones in the gonads and suprarenal glands: indeed, its use as a contraceptive is also considered able to prevent cancer risks linked to the use of estrogens.

From the vascular point of view, it keeps cholesterol levels lower and, thanks to its vasodilatory effect, it reduces body temperature and arterial pressure both in normotensive and hypertensive individuals.

How can we increase our body’s production of melatonin? In a natural way, it is possible by controlling our daily diet. Do you remember melatonin’s precursor, tryptophane?  It is an amino acid that is contained in protein rich foods, especially pulses and seeds, hence one’s diet should not lack this amino acid; carbohydrates also play an important role, because if consumed in the right amount, in the evening they favour the entrance of tryptophane in the brain (this is the reason why perhaps not consuming carbohydrates in the evening may hinder sleep). However, it is necessary to eat with moderation because a low calorie intake favours the production of melatonin (hence, longevity).

With regards to physical exercise, it is advisable not to train too intensively late in the evening because it has been demonstrated that an intense physical training, even if for only 20 minutes, reduces the secretion of melatonin for the subsequent three hours and favours the production of cortisol, which, as you may remember, contrasts with melatonin.

Another two rules: during the day, try to stay in intense light for a couple of hours and make sure that you go to bed before midnight with all lights off.

However, in certain cases our body cannot produce enough melatonin. There could be several reasons for this: age, abuse of alcohol and caffeine, electromagnetic and radioactive pollution, alteration of the sleeping-waking or light-darkness rhythms, such as those who work on night shifts. Well, in all these or other cases, using melatonin as a supplement may be very useful.

The recommended dose is 1 to 5 mg per day based on age. It is advisable to start first with a lower dose and, if necessary, gradually increase up to 10 mg/day.

Take it approximately 2 hours before going to sleep, possibly at the same time every day and, unless absolutely necessary, only in winter and summer, interrupting its use in the in-between seasons.

(17)