Why Do People Get Hangovers?

Have you ever watched a TV show or movie where a character drinks too much alcohol one night? And the next day, they wake up with a hangover? This often seems funny on the screen. But in real life, it is pretty unpleasant! 

A hangover can leave a person with many uncomfortable symptoms.Here are a few examples:

• a pounding headache (that’s the symptom you often see in movies)
• dry mouth
• nausea
• sensitivity to light
• irritable mood
• trouble concentrating

Let’s look at some theories about why hangovers happen.

What causes a hangover?

Scientists aren’t sure what exactly causes a hangover. But there are a few well-known theories. One theory is that hangovers are caused by dehydration. That’s a lack of water in the body.

In order to reabsorb water, the kidneys need a hormone called vasopressin. Without vasopressin, the body expels water in the form of urine. Alcohol is linked to suppressing vasopressin production in the brain. This supports the idea that when a person drinks alcohol, they get dehydrated.  But studies have shown that the degree of vasopressin-suppression caused by alcohol may not be enough to cause hangover symptoms at all! 

Did you know?

The technical term for having a hangover is “veisalgia.”

Another popular theory is that the breakdown of alcohol by the body produces a toxic substance called acetaldehyde. This symptom may be linked to hangover symptoms. The liver is responsible for breaking alcohol down in the body. 

Liver breaks alcohol down in a multi-step reaction.

First, an enzyme called alcohol dehydrogenase (ADH) breaks ethanol down in the liver. Ethanol (CH₃CH₂OH) is the chemical name of the alcohol people drink. This reaction creates the intermediate product, acetaldehyde (CH₃CHO). 

Next, the enzyme aldehyde dehydrogenase (ALDH) breaks down acetaldehyde. This results in acetate (CH₃COO-).

Finally, scetate is then further broken down into carbon dioxide (CO₂) and water (H₂O). It is expelled from the body. 

Some studies suggest that acetaldehyde concentration in the body is linked to a hangover. But hangovers are more likely linked to underlying immune factors, and the body’s overall health.

Another theory involves cytokines. Cytokines are proteins released by the cells. They assist in cell communication. Typically, they are linked to the immune system. They transmit information and facilitate the body’s reaction when you get sick. Studies have also found that drinking alcohol can cause changes in cytokine concentrations in the immune system. So when a person drinks alcohol, their body’s cytokine concentration goes up. This disrupts the body’s ability to communicate properly. The body may begin to think it is sick. And what happens when your body thinks it is sick? You get symptoms like nausea, headaches, and fatigue. 

Finally, further studies suggest that chemicals called congeners might affect how bad a hangover gets. Congeners are trace chemicals in alcoholic beverages. They result from fermentation. They can break down into toxic chemicals in the body, and may be the cause of hangover symptoms. 

Did you know?

Red wine and dark liquor, such as whisky, have the highest levels of congeners. This may be why hangovers from these drinks can be especially tough!

What is the best cure for a hangover?

First of all, be sure to avoid alcohol if you’re not of legal age.

But for people who are of legal age, the best way to avoid a hangover is to drink moderately in the first place. Limit how much alcohol you drink at one time.

Can drinking water cure or prevent a hangover? There is limited evidence that it can. But water does help treat some of the symptoms, such as dry mouth and headaches. Also, eating foods high in potassium, such as bananas, can help correct ionic imbalances in the body. People lose vitamins through urination. But in general, foods high in vitamins can help replace lost vitamins. They can also help with alcohol detoxification. Finally, foods that have a high amount of the amino acid cysteine help break down acetaldehyde. Eggs are an example. This may explain those hungover brunches you see on TV!