With the festive season approaching fast you might find yourself consuming a few drinks here and there. Have you ever wondered why some people feel absolutely awful the morning after a couple of drinks and why some react terribly to alcohol? Read on to discover the science behind it and how you can try avoid hangover from hell.


What is a hangover?

First things first, the hangover. Most of us have probably been there after a boozy night; nausea, fatigue, dehydration, headache and the feeling of regret. The hangover is a constellation of death-like symptoms resulting from the processes the body undergoes after consumption of alcohol.

The duration and severity of the hangover depends on a number of factors, including the amount and strength alcohol consumed and the rate of it’s breakdown, with great variance from person to person. Alcohol is a psychoactive and toxic substance that affects multiple bodily systems and once consumed, it has to be converted into non-toxic forms. Here comes the science.

When alcohol is consumed, it’s converted into acetaldehyde via the enzyme alcohol dehydrogenase (ADH). Acetaldehyde is a toxic metabolite and excessive buildup can lead to sickness, skin flushing and headache. Acetaldehyde is then converted into the non-toxic acetic acid, via the enzyme aldehyde dehydrogenase (ALDH). Following?.. However, there is a genetic variance in the type of ALDH enzyme you might have. Research has shown that People of far east Asian descent are more likely to have a mutated version of ALDH, resulting in greater accumulation of the toxic acetaldehyde when consuming alcohol (as the body is less capable to remove it from your system.) This can then lead to the aforementioned symptoms.


Intolerance or allergy?

Other than genetic differences, some people are actually intolerant to chemicals and preservatives that are found in alcoholic beverages, notably sulphites and histamine. Some studies have shown that asthmatics can be especially sensitive to sulphites, which can cause airway irritation and lead to wheezing. These intolerances are often confused with alcohol allergy, which is quite rare. So how do you determine the difference between an alcohol intolerance and a bad hangover? The key is understanding the timeframe in which changes occur. Hangovers effects are generally felt the morning after a night of drinking, whereas intolerances impact an individual much quicker, often within minutes to hours.


Prevention is better than cure. Here’s 3 tips to help you avoid bad hangovers:

1. Keep track of your drinks throughout the night - remember the recommended weekly limit is 14 units of alcohol

2. Avoid drinking on an empty stomach and limit your drinking.

3. Drinking plenty of water between or with alcoholic drinks and before bed can help prevent dehydration.


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Dr Zobir Alexander | Well Squared
Dr Zobir Alexander, MB ChB, BSc (Hons) - Senior Writer
November 12, 2022 — Dr Zobir Alexander