Everything you need to know about hangovers

Anyone who enjoys a drink every now and then will understand the devastation that follows a heavy night: cue the dreaded hangover. Alcohol can have a range of effects on the body, from the shakes of alcohol withdrawal to aches and pains, but whilst you’re recovering in bed, what’s actually going on inside you? This article will tell you everything you need to know about hangovers, including how long they last, why they happen in the first place, and why certain people may be more prone to them than others.

Hangover symptoms

Alcohol can affect your body in many ways, which can lead to unpleasant symptoms the following day. These symptoms can vary from person to person depending on numerous factors (which we’ll cover shortly), all of which can range in intensity – some may feel slightly unwell, others may be bed bound.

You’ll generally start to notice the following hangover symptoms when your blood alcohol content drops – when it’s either at or close to zero. By the time you wake up after a night of excessive drinking, the symptoms will likely be in full effect.

Typical hangovers symptoms include:

• Fatigue
• Muscle weakness
• Thirst
• Headache
• Muscle aches
• Nausea
• Stomach pain
• Vertigo
• Light sensitivity
• Increased blood pressure
• Dry mouth
• Vomiting
• Poor sleep
• Inability to concentrate
• Rapid heartbeat
• Mood disturbances, including depression, irritability and anxiety

Why does alcohol cause a hangover?

Alcohol can cause a hangover due to the following reasons:

• Dehydration: Alcohol is a diuretic, which explains why you may feel the need to wee more often after a drink. Therefore, you’re more likely to feel dehydrated the following morning, which can lead to headaches, dizziness, and excessive thirst.
• Electrolyte imbalance: Alcohol consumption causes electrolyte imbalance, which explains why you may experience headaches, weakness, and irritability when hungover.
• Blood vessel dilation: Blood vessel dilation (vasodilation) – which is when your blood vessels widen – happens when you drink alcohol. This is associated with headaches – a common hangover symptom.
• Low blood sugar: As alcohol consumption limits the production of glucose in the body, you may display symptoms that are associated with low blood sugar (hypoglycemia). This includes fatigue, irritability, and dizziness.
• Gastrointestinal irritation: Alcohol increases acid production in your digestive system, so depending on how much you drink, it can affect the speed that food matter travels through your gastrointestinal tract. This can cause nausea, diarrhoea, and vomiting.
• Poor quality sleep: Drinking alcohol prevents high-quality sleep, which can cause you to wake up multiple times in the night, so you may feel drowsier than normal the following day.
• Congeners: The minor compound found in alcohol, congeners, also play a part in causing a hangover. We’ll cover this in more detail below.

How long do hangovers last?

Whilst alcohol can have a longer term impact on your body, your hangover symptoms should subside on their own within 24 hours – however, this can vary from person to person. One study found that hangovers generally follow one of three time patterns: a continuous decline hangover (Severity Type 1), a steady state hangover (Severity Type 2), and an inverted U-shaped curve hangover (Severity Type 3). These hangover severity types appeared to be related to the amount of alcohol consumed, and the severity of symptoms. For example, participants who reported gastrointestinal complaints were more likely to experience an inverted U-shaped hangover (Severity Type 3).

What are congeners?

Congeners are the minor compounds that occur naturally in alcohol beverages as a result of the distilling and fermenting processes. The most common of these include methanol, tannins and acetaldehyde, but congener content can vary between different alcoholic beverages. It’s suggested that it takes fewer drinks with a high congener content to result in a hangover, and that hangover can be more severe.

Congeners are found in most alcoholic drinks, but by opting for drinks that are low in congeners – such as light-coloured beer or clear liquor – you could decrease the severity of your hangover.

Which drinks are low in congeners?

Drinks that are low in congeners include:

• Vodka
• Gin
• Other clear spirits

Which drinks are high in congeners?

Darker drinks are generally higher in congeners, such as:

• Red wine
• Dark spirits

Are some people more likely to develop hangovers than others?

So, why are certain people prone to hangovers, and others can get away with little more than a headache? There are certain surprising factors that could increase the risk of developing a hangover, such as:

• Personality: One naturalistic study suggests that those who are shy are more likely to experience anxiety when hungover, however little research has been conducted in this area.
• Age: It’s thought that age could influence the effects of alcohol, with one study suggesting that younger drinkers experience more severe hangovers.
• Genetics: A study, in which Australian twins took part in telephone interviews, revealed that genetic factors accounted for 45% and 40% of the variation in hangover frequency of men and women, respectively. Not only this, alcohol dependence (alcoholism) has been suggested to run in families – although this alone doesn’t sufficiently demonstrate that genetic factors increase the risk. 
• Sex: In one study, women reported higher severity scores on nausea, tiredness, weakness, and dizziness than men. On the other hand, the presence of heart racing, confusion, and sweating were reported significantly more frequently by men.
• Drinking combined with other factors: Smoking whilst consuming excessive amounts of alcohol has been found to affect hangover sensitivity and severity.

How to “cure” a hangover

Unfortunately there is no “cure” for a hangover. But if you find yourself battling against one, there are a few things you can do to make it a little more bearable. This could include:

• Drinking plenty of water to rehydrate.
• Eating protein and fat will help to stabilise your blood sugar. Avoid sugary foods and refined carbs as these can spark an insulin response and then crash, making you feel worse.
• Consuming sodium-rich liquids to balance electrolyte levels and boost minerals – such as soup broth.
• Going back to bed, as hangover symptoms are made worse by a lack of sleep.

How to prevent a hangover

Although the only real “cure” for a hangover is avoiding heavy drinking sessions, to decrease your likelihood of dealing with a nasty one in the morning, try doing the following:

• Eating a meal before you drink alcohol can slow down the rate that alcohol is absorbed into the bloodstream
• Choosing light-coloured drinks, as these tend to have a lower congener content
• Avoiding smoking, as this could intensify your hangover
• Drinking plenty of water steadily throughout the night, consuming a glass between each alcoholic drink, and one before you go to bed
• Getting a good night’s sleep

Take away

For those that enjoy an alcoholic beverage every now and then, there are ways to drink safely – which will, consequently, reduce your risk of waking up with a bad hangover the following day. Everyone has a different tolerance level – which can vary based on a variety of factors – so don’t feel pressured to consume more in an attempt to catch up with friends. Know your limits, choose your beverages carefully, and try to follow the above steps before and after drinking to avoid the next day being a writeoff.

Looking for ways to be healthier all round? Download the Evergreen Life app today, and get started straight away on your wellness journey.

[1] National Institute on Alcohol Abuse and Alcoholism. (2021). Hangovers. National Institute on Alcohol Abuse and Alcoholism.

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