Alcohol and sleep

The impact of alcohol on sleep

Drowsiness, tiredness, the urge to sleep after a few drinks. Despite these sensations associated with drinking alcohol, it's common to feel tired the next day.

In fact, with low to moderate alcohol consumption, researchers observe a sedative effect, which leads to falling asleep faster.

During the first half of the night, alcohol leads to an increase in the duration of light slow-wave sleep, and then tends to reduce or even suppress REM sleep (the shortest phase of sleep, characterised by intense brain activity).

Over the course of a night, alcohol reduces the deep sleep cycles and disrupts sleep in general through night-time awakenings.

All this is explained by the fact that alcohol acts on various mechanisms linked to sleep.

First of all, alcohol raises your body temperature.

Yet in order to fall asleep, our body needs to gradually lower its temperature. Alcohol therefore tends to prevent you from falling asleep.

Next, alcohol has a negative impact on the secretion of many molecules, such as GABA. This is a molecule that allows the body to relax, which makes it easier to fall asleep.

Alcohol consumption can also trigger or worsen certain sleep disorders.

Alcohol mainly affects snoring and sleep apnoea.

So even in small doses, alcohol impacts our sleep by lowering its quality, shortening its duration and increasing the number of night-time awakenings.

Disrupted sleep affects our daily life and leads to noticeable consequences such as tiredness and reduced alertness, but it can also impair the proper functioning of our body (such as hormone secretion).

For your health, drink alcohol in moderation.

Sources:

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