Serotonin and melatonin are words that you may have heard bandied about. Both are natural hormones produced in the brain, and are the two vital chemicals associated with sleep. They are intimately linked – serotonin is the precursor of melatonin. Without enough of either, we don’t sleep. It’s as simple as that.
Serotonin is one of the most important brain chemicals. You need it to sleep and to be happy. Indeed, serotonin is our very own Prozac (Prozac and other anti-depressants are all specific serotonin-boosters). Lack of serotonin not only results in insomnia but also anxiety and depression these are two of insomnia’s most common bedfellows and various mood disorders from panic attacks, irritability, anger, PMT, SAD (seasonal affective disorder) and more. People with low self-esteem or guilt complexes, or who worry or are obsessive (sound familiar?) often have low serotonin levels.
There is an important gender difference here, with men getting the better deal. Men produce serotonin twice as fast as women, which mean they have the ability, generally, to recover from any shortfall more quickly. Women produce up to a third less than men: it seems we are programmed to be moody, which statistics confirm. In addition, low serotonin in women is associated with depression and anxiety; in men it’s associated more with aggression and alcoholism. Add to this the fact that low estrogens levels also result in low serotonin levels
Although serotonin is produced in the brain, around 90 per cent is found in the gut. It plays a role in appetite control, and if you suffer from carbohydrate cravings, this may indicate low serotonin levels. Your heart is also partly dependent on serotonin, so that lack of serotonin can affect both your digestion and your heart.
Serotonin is produced in the brain from tryptophan, one of the essential amino acids you need to take in via your diet. Light affects its levels (more light, more serotonin). Exercises and oxygen also help to boost its production. A poor diet, alcohol, caffeine and the artificial sweetener aspartame all rob you of your precious serotonin, as does stress.
This is because in an effort to keep you calm, your brain releases more serotonin, diverting its precious supplies to cope with the stress rather than to promote sleep. Apart from a lack of tryptophan, Patrick Holford in Optimum Nutrition for the Mind, identifies the main causes of serotonin deficiency as: lack of oestrogen (women) or testosterone (men), not enough light, not enough exercise, too much stress (especially for women) and finally, not enough co-factor poor vitamins and minerals.
Nor does it end there. As one sleep scientist explains, serotonin is talked about as if it were a simple neurotransmitter, when in fact it’s a lot more complicated. It has at least 8-12 different receptors, with different associated control mechanisms. Simple increases and decreases in serotonin also have different effects on bodily systems. No wonder your sleep suffers. It’s easy to see, too, how an insomniac quickly succumbs to other negative side-effects of an imbalance of serotonin let alone whatever is happening with your melatonin and stress hormones.
Anyone who has insomnia or who has tried to alleviate jet-lag will have heard of melatonin, nature’s soporific sleep-inducing hormone, produced in the tiny pineal gland at the base of the brain, and which was only discovered 50 years ago. Melatonin orchestrates sleep by preparing the body to sleep. As already discussed, its production is regulated by light. It’s produced at night, triggered by the fading light as the sun sets.
When dawn comes, melatonin level drop quickly, and are virtually undetectable during the day. Overnight urine contains a high concentration of melatonin, which is why some Indian Holy men drink it (to keep themselves calm). Not surprisingly, we produce more in winter than summer. A rise in melatonin signals a decrease in body temperature (which promotes, sleep) a decrease in melatonin signals a rise in body temperature (wakefulness).
How much light affects melatonin production differs from person to person for example, some people shut down production virtually immediately if exposed to unexpected bright light during the night; for others this takes up to an hour. Children produce most melatonin; this drops at puberty and wanes with age, dropping sharply at the onset of middle-age. Increasing your melatonin levels, usually by supplementation, is a well-known ‘cure’ for jet-lag and insomnia, and has also been hailed as a means of combating the ageing process, as it is a potent antioxidant and scavenger of free radicals, and a powerful immune system-enhancer. In short, we all need lots of lovely melatonin.
Melatonin is produced from serotonin. The only sure way to know whether you are making enough is to pay for a private saliva test. Caffeine, tobacco, alcohol, dark chocolate, certain drugs – aspirin, antidepressants and tranquillizers – and being close to electrical appliances will all rob you of melatonin.
There are four ways to try and boost melatonin levels (and hence improve your sleep):
- Using light to stimulate production
- Taking melatonin supplements
- Taking serotonin supplements
- Increasing tryptophan (which converts to serotonin, which converts to melatonin) either in your diet or by taking supplements