why does alcohol dehydrate you - An image of a woman drinking a glass of water

From social gatherings and personal celebrations to unwinding after a long day, alcohol plays a key role in many people’s lives. But have you ever wondered why you feel so thirsty after a night of drinking? Here, we delve deep into the science behind alcohol and dehydration, the bigger effects this can have on you physically and mentally, and offer some much-needed tips to help mitigate the effects of alcohol.


Does Alcohol Cause Dehydration?

In short, yes. But to understand this fully, it’s important to look at alcohol’s diuretic nature. When alcohol is consumed, it interacts with the body’s antidiuretic hormone and its production. This hormone is normally responsible for regulating water balance and retention in the body and signals the kidneys to function properly and retain water. But when alcohol is present, the hormone becomes suppressed, which is why some people may find they have the urge to urinate more after alcohol.

What’s more, as the liver processes and metabolises alcohol, it creates a compound called acetaldehyde, which is also known for its dehydrating effects. This, combined with the suppressed hormone, makes the body prone to dehydration both during and after alcohol consumption.

Alcohol doesn’t only affect hydration levels in the body but also the balance of electrolytes, which is essential for several bodily functions. Electrolytes include magnesium, potassium and sodium and play a key role in nerve transmission, cellular function and muscle contraction. Alcohol and alcohol-induced dehydration can lead to imbalances within these, resulting in weakness, fatigue and muscle cramps – all of which can be dangerous if they’re not dealt with appropriately.


What Causes Alcohol Dehydration?

The liver is responsible for processing substances in our body, and it’s no different when alcohol is present. But as it breaks down alcohol, acetaldehyde is created, which is essentially a toxin that requires more water in order to be eliminated. This uses up the body’s excess water reserves and adds to the dehydrating effects of alcohol. At the same time, alcohol causes the kidneys to increase their urine production, which also adds to dehydration.  Alcohol not only contains dehydrating factors but also causes dehydrating toxins and excess urination. Put simply, it’s like a vicious cycle.

Studies also show that alcohol dilates the blood vessels, which leads to an increase in blood flow to the skin. While this typically makes individuals feel warmer, it can also result in sweating, and this fluid loss contributes to overall dehydration. As well as this, alcohol impairs the body’s ability to identify and respond to dehydration as it suppresses an individual’s sensation of thirst. In short, this means that many people feel the need to consume less water than usual, which again can increase the risk of dehydration and its overall effects.

Finally, we know that drinking alcohol causes the body’s water distribution to be shifted. Water is moved around the body’s cells to extracellular space, affecting cellular function and increasing the overall reduction in the total body water content, again having a direct effect on hydration levels.

Common Signs of Alcohol Dehydration

Some of the most obvious signs of dehydration caused by alcohol include thirst, headaches and dark yellow urine. However, various other signs might not be as well known. This includes fatigue, confusion and dizziness. These symptoms are likely to be masked by alcohol consumption, which can make them more difficult to spot, too. Being aware of these common signs, as well as the more unusual ones, can help you to be proactive when it comes to your own alcohol consumption and also help someone else in need. Remember, you shouldn’t just focus on rehydrating but instead, look for the smallest signs that your body needs more water.

Alcohol dehydration is also known to exacerbate common hangover symptoms, including headaches, sickness and general discomfort. This is why it’s essential to drink water, consume electrolyte-rich foods and beverages, and get some rest if you believe you are suffering from alcohol dehydration and a hangover.


Long-Term Effects of Chronic Dehydration

Occasional dehydration from alcohol might leave you feeling unwell for a short period of time, but excessive and prolonged dehydration from alcohol use does present a few more serious risks. This is because it can begin to affect organs and their function, skin health and overall well-being. For this reason, you must look out for the signs of alcohol dehydration and take a proactive approach to maintaining appropriate hydration levels before, during and after consuming alcohol.


Hydration Strategies During Alcohol Consumption

Here, we reveal some best practice advice to ensure that you stay well-hydrated and safe when before, during and after alcohol consumption.

  • Be sure to eat healthily and drink water before, during and after you have drunk alcohol. Electrolyte-rich drinks like sports drinks can help you replenish any lost nutrients the next day. Fruit and vegetables, with their high water content, can also help you to retain much-needed energy and hydration.
  • Intersperse alcoholic drinks with water and soda drinks to help stay hydrated.
  • Alcoholic drinks that require mixers, such as soda water, can help you to reduce any effects of dehydration.
  • Consider setting limits for your alcohol consumption to prevent excessive fluid loss.
  • Remember that moderation is key, and try to pace your alcohol intake.

By incorporating these strategies into your alcohol consumption, you can make more mindful choices when it comes to alcohol and mitigate the risk of dehydration.


How We Can Help

There is a clear link between alcohol and dehydration, but armed with the above knowledge, you can hopefully take a more informed approach to your drinking. However, in Step 1, Recovery, we know it isn’t always that easy.

If you or someone you know is struggling with their alcohol intake, just know that we’re here to help you. Our team provides the tools, resources and information you need to be able to make decisions about your well-being and drinking. So, if you have any questions or concerns, just remember that we’re here today.