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What's going on when you're hungover?

Party season is now behind us. Many of us will have consumed a tipple or two, and some of us will have had a hangover. Alcohol is a very widely consumed drug. In fact, the Global Drugs Study 2018 found that 98.9% of respondents had consumed alcohol.

A hangover, defined by the Oxford English Dictionary as “a severe headache or other after-effects caused by drinking an excess of alcohol”, are known the world over, as are the acute effects thereof. In short, excessive consumption of alcohol can make you feel dreadful. But what’s really going on? Let’s break it down.

You feel dehydrated.

One of the most commonly known effects of drinking too much alcohol. It’s a diuretic and urine excretion increases by 10ml for every 1g of alcohol consumed, hence the queues in toilets!

Alcohol also reduces the production of a hormone called vasopressin which tells your kidneys to reabsorb water rather than flush it out through the bladder. This means that the bladder fills up quickly.

You feel nauseous, weak and have a headache.

A compound called acetaldehyde is created when alcohol is broken down in the liver, which is highly toxic. An enzyme and another substance called glutathione break down acetaldehyde, but only if you only have a few drinks. The liver’s stores of glutathione run out quickly, so if you drink too much, acetaldehyde will build up causing headaches, nausea and vomiting.

Interestingly, women have lower levels of enzymes and glutathione, which means it takes longer for their bodies to break down alcohol. Moreover, many people of oriental origin have a less efficient form of ethanol dehydrogenase, an enzyme necessary for alcohol processing in their liver, meaning that many feel drunk very quickly.

What else is going on in the liver?

Alcohol prevents the liver from producing glucose, so the body uses other stores of it called glycogen. As a result, insulin is secreted which leads to low blood sugar. Lack of this key energy source is at least partly responsible for the weakness, fatigue and lack of co-ordination the next morning.

Your digestive system behaves differently.

Put simply, alcohol irritates it.

It promotes secretion of gastric acid in the stomach, eventually causing gastritis (inflammation of the stomach lining). This triggers stomach pain, vomiting, diarrhoea and, in heavy drinkers, even bleeding.

Even in small quantities, alcohol can interfere with gastric and intestinal motility, slowing down transit time. This may cause feelings of being full and stomach discomfort.

Your stomach is also affected by glutamine levels. Alcohol inhibits the production of this natural stimulant, which works to keep you awake. However, when you stop drinking, your body reacts by overproducing glutamine. This prevents you from sleeping deeply, but also causes stomach irritation and general malaise.

You feel low.

The depressive nature of alcohol is significant. The spike in positive neurochemicals such as serotonin, GABA, dopamine etc. leaves us feeling good while we’re intoxicated, however when we stop drinking and become hungover, the levels of these chemicals drop causing depression and anxiety.

A 2003 study into alcohol withdrawal with a focus on alcohol-dependent individuals found significant decreases in serotonin (known as the happiness chemical) during the 14 days after alcohol consumption, not just in that hangover period. In fact, serotonin levels didn’t return to normal even after this 14 day period (Patkar AA et al., 2003).

To clarify, those who have hangovers but who aren’t alcohol-dependent also experience a drop in serotonin levels. And the more often we drink, the greater the impact.

A third reason why alcohol can cause anxiety and depression is centred on a process called neurogenesis: the production of new brain cells. This takes roughly 4 weeks and occurs in the hippocampus; a part of the brain associated with emotions amongst other things. Alcohol significantly affects the hippocampus and reduces neurogenesis. This increases depression (Johnson et al, 2006).

Whilst this article is meant to be informative and educational about what goes on in your body, if you feel as though you do have an unhealthy relationship with alcohol there are steps that you can take. It’s our job as a responsible organisation to take a few minutes now to outline these for you.

Firstly, do you:

· Often feel the need to drink?

· Get into trouble because of your drinking?

· Often have others warning you about how much you're drinking?

· Think your drinking is causing you problems?

If you identify with these feelings, seek support from your GP or a mental health professional. Alternatively, you may want to reach out to a local support group.


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