Dry January: The Science Behind Alcohol

by Lucy Bell-Young

Dry January is a public campaign, created by Alcohol Concern, where people all over the UK abstain from alcohol for the whole month. In recognition of this event, we thought it would be interesting to delve beneath the surface and discover the science behind the effects of alcohol.

It is time to face the January blues. Christmas is over. New Year has been and gone. We shed a tear as decorations were packed away, leaving the house feeling unbearably plain; and we flinched from an inward shiver of embarrassment as we cleared out the empty bottles of liquor. But this month also signals the beginning of a nationwide campaign: Dry January.

For many participants, the holiday season has been punctuated with frosty G&Ts and copious amounts of mulled wine as they geared themselves towards a month of total sobriety. But does quitting alcohol for a month really have an impact on your health? To answer that question, we must first look into the effects alcohol has on our bodies.

Alcohol bottles on wooden shelf behind bar
Image courtesy of https://drughelpline.org/alcohol-hotline/

Alcohol and the Body

We all know that alcohol has some pretty noticeable physical effects on the body. But how do we get intoxicated to begin with?


Intoxication occurs when we consume more alcohol than our body can metabolise, and this is actually very easy to do. Once we consume an alcoholic beverage, 90% of it travels to the small intestines where it is absorbed into the bloodstream. Meanwhile, it is the liver’s job to break it down. However, the liver can only metabolise 15mg/dL every hour. This is the equivalent to approximately one drink per hour.

When this limit is exceeded, alcohol accumulates in the bloodstream. This is what kick-starts symptoms of intoxication.


In the liver, the alcohol is first metabolised by an enzyme called alcohol dehydrogenase. This creates a toxic compound known as acetaldehyde, which is the culprit behind hangover symptoms.

Acetaldehyde is then metabolised by another enzyme, aldehyde dehydrogenase, and turned into acetic acid, which is non-toxic and also referred to as vinegar. This final stage features a key team player, a substance called glutathione which is attracted to acetaldehyde and helps to form acetic acid. When only a small amount of drinks have been consumed, this process works so well that acetaldehyde only has a very short amount of time to do its damage before being removed.

However, when larger amounts of alcohol are consumed, the liver’s stores of glutathione deplete rapidly. As the liver tries to create more, acetaldehyde begins to build up in the body. When this toxin is left in the body for longer periods of time, it results in headaches and nausea.

Close up of a boy drinking beer from a pint glass

Alcohol and the Brain

The symptoms of intoxication at the beginning of a night out may manifest themselves in that text you definitely shouldn’t have sent, or your sudden desire to be as close to people as possible. In other words, your inhibitions are lowered.


We experience reduced inhibitions because alcohol is able to activate GABA receptors. These are your inhibitory, or ‘STOP’ neurons. By increasing the production of these, alcohol is ultimately able to decrease the overall activity of the brain.

Another way alcohol impacts our brain is through glutamate receptors. Unlike GABA receptors, glutamatergic neurons are your excitatory, or ‘GO’ neurons. While alcohol activates GABA receptors, it actually inhibits glutamate receptors. As before, this decreases activity in certain areas of the brain.

Regions of the Brain

The prefrontal cortex is one area of the brain that suffers from decreased activity during alcohol consumption. This region of the brain is responsible for planning cognitive behaviour, decision making, and moderating social behaviour. When the activity here decreases, then, it is easy to correlate intoxication with lowered inhibitions.

Approximately 5 alcoholic drinks is the equivalent to a blood alcohol concentration of 50mg/dL. This is more than triple the limit of what the liver can effectively metabolise.

At this stage, consumers often experience incoordination. This happens because of the effect alcohol has on the cerebellum, a region of the brain that regulates motor movements and coordinates balance, posture, and speech. This is why a symptom of intoxication is slurred speech and a lack of balance; the cerebellum is especially sensitive to the effects of alcohol.

Feel Good Factor

So if alcohol has such negative effects on our brains, why does it feel so good to drink? Even if, in our drunken stupor, we are aware that we’ll regret it if we drink anymore, the effects of alcohol still keep us reaching for another glass.

This is because alcohol actually increases levels of dopamine in our brain. These are your feel good neurotransmitters, and they can also be increased by exercising, listening to music, and even eating chocolate. In this scenario, dopamine actually causes the reinforcing effects of alcohol, and this is what keeps you wanting more.

Effects of Dry January

Many of us greeted 2018 with a hangover. For people all over the UK, this marked their final blow-out before beginning Dry January. But does this month dedicated to sobriety actually have an effect on our health?

Now that we know what impact alcohol has on our body, the answer may appear to be a resounding yes. Indeed, in previous years it has been recorded that Dry January had several benefits on the health of participants:

  • Fat accumulation in the liver, which preludes liver damage, was reduced by 15% on average
  • Total blood cholesterol, which can cause heart disease, decreased by 5%
  • Blood glucose levels also dropped by 16%
  • Quality of sleep improved

As we can see, Dry January definitely has positive effects on your health in the short-term, and it is always good to reduce your amount of alcohol consumption. However, since Dry January is a relatively new phenomena, it’s not yet known whether these specific health benefits will persist. If you rarely drink, for example, there may not be any major difference in your health before and after Dry January.

Can Anyone Participate in Dry January?

Unfortunately, no. For heavy drinkers or those who suffer from ADS (Alcohol Dependence Syndrome), giving up alcohol cold-turkey for a month could be extremely dangerous. Withdrawal symptoms could include disrupted sleep, hallucinations, vomiting, and even seizures. This is because alcohol dependency is one of the only types of addictions that has potentially fatal withdrawal symptoms.

In fact, studies have shown that the less you drink in general, the more successful you’re likely to be at completing Dry January. If you’re a heavy drinker trying to stop, taking at least 2 dry days a week all year round will have more beneficial effects on your health than Dry January.

However, Dry January isn’t just about improving your own personal health. It’s about participating in a nationwide effort to help those who struggle with alcohol.

Empty wine glass and empty whisky glass on stairs

Whether or not Dry January has long term health benefits, it goes without saying that it is an incredible event that raises awareness of and support for alcohol abuse. If you feel like challenging yourself, why not give it a go? It’s never too late! You can find out all about it on the Alcohol Concern website. And if you’re not participating – remember to drink responsibly!


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