Why do people get hangovers after drinks the night before?

Answer 1

The hangover is a mild manifestation of alcohol withdrawal. In the earlier stages, it is the all too familiar "hangover headache." This is more likely related to vasular changes and has nothing to do with the brain. The brain itself has no pain receptors. So, any headache pain must be from nerves surrounding the lining, skin, vessels, or muscles. Although the alcohol has been eliminated, the body's chemical balance has been upset, digestive organs have been abused, and an overpowering fatigue is felt. There is lack of consensus among researchers on the cause of hangovers. The explanations most frequently cited are decribed below. (See the rest at the link below)

Answer 2

There are several things going on in your body after a night of drinking alcohol - all of which contribute to the crappy feeling commonly known as a hangover.

First of all, alcohol is a diuretic - drinking causes the body to become dehydrated. Dehydration can make you feel tired and dry-mouthed and give you a good-sized headache.

Second of all, what we call "alcohol" is really a specific type of alcohol called "ethanol". Your body breaks down ethanol in the liver - using special enzymes that are created in the liver's cells. When the liver is working overtime to break down ethanol, it's not doing a very good job pumping out glucose to the body's tissues - especially one of the most greedy consumers of glucose - the brain. Because glucose is the source of the brain's energy, a shortage of glucose can cause fatigue, attention deficit, weakness and irritability.

Thirdly, the alcohol we consume contains various amounts of a substance known as congeners - these congeners are by-products of the fermentation of alcohol. The more congeners in your beverage of choice, the worse your next-day hangover is likely to be. The so-called "dark" spirits, like brandy, red wine and whiskey contain more congeners than light spirits, like rum, vodka and white wine, so a night of drinking Jack Daniels is going to mean there's hell to pay in the morning.

Scientists debate the impact of other factors, but the 3 above are probably the "main" influences on that crappy next day feeling.

Answer 3

The alcohol causes dehydration which causes the brain to swell. Drink a lot of water before bed after drinking alcohol, you will likely prevent hangovers.

Answer 4

#1 Reason for a hang over is dehydration

Alcohol acts as a diuretic, which means that it increases the release of urine from the body. This is because your kidneys and liver require water to dilute and process the toxins. When you drink alcohol, your body actually requires more water than usual in order to perform this function efficiently. If water and fluids are not readily available to aid in this detoxification process, the body redistributes whatever water is available. All parts of the body are affected by this redistribution of fluid, even the brain. And you wonder why your head hurts!
Other reasons...

When you go to sleep with a high amount of alcohol in your system, your brain is unable to enter the REM (Rapid Eye Movement) stage of sleep. Without the REM stage of sleep, your brain is unable to dream and achieve the relaxation it needs. So while you may end up sleeping the whole night and half the day away, your brain did not get the rest it so desperately needs.
Your body attempts to protect itself by producing enzymes to metabolize and remove the toxins from your body. But when the toxin level exceeds your body's ability to metabolize them in an efficient manner, you experience the unpleasant and classic symptoms of a hangover. The excess toxins may irritate your stomach, cause you to vomit, and in general, make you feel ill.

Answer 5

A big part of it is that drinking liquor tends to dehydrate you.

Since hearing this, I always make a point of drinking lots of water before going to bed if I have had a couple of drinks. I haven't had a hangover since the early 1990s.

Answer 6

Hangovers are multi-causal. Ethanol has a dehydrating effect (such substances are known as diuretics), which causes headaches, dry mouth, and lethargy. Dehydration causes the brain to shrink away from the skull slightly. This can be mitigated by drinking plenty of water during and after consumption of alcohol. Alcohol's impact on the stomach lining can account for nausea. Due to the increased NADH production during metabolism of ethanol by alcohol and aldehyde dehydrogenases, excess NADH can build up and slow down gluconeogenesis in the liver, thus causing hypoglycemia.

Another factor contributing to a hangover is what results from the breakdown of ethanol via two chemical reactions, aided by enzymes produced by the cells of the liver. Ethanol is converted to acetaldehyde by the enzyme alcohol dehydrogenase, and then from acetaldehyde to acetate by the enzyme acetaldehyde dehydrogenase. Acetaldehyde and acetate are both mildly toxic, contributing to the hangover.

The two aforementioned reactions also require the conversion of NAD+ to NADH. With an excess of NADH, the lactate dehydrogenase reaction is driven to produce lactate from pyruvate (the end product of glycolysis) in order to regenerate NAD+ and sustain life. This diverts pyruvate from other pathways such as gluconeogenesis, thereby impairing the ability of the liver to supply glucose to tissues, especially the brain. Because glucose is the primary energy source of the brain, this lack of glucose contributes to hangover symptoms such as fatigue, weakness, mood disturbances, and decreased attention and concentration.

Finally there are various nervous effects. The removal of the depressive effects of alcohol in the brain probably account for the light and noise sensitivity.

In addition, it is thought that the presence of other alcohols (such as methanol and fusel oils), by-products of the alcoholic fermentation also called congeners, exaggerates many of the symptoms; this probably accounts for the mitigation of the effects when distilled alcohol, particularly vodka, is consumed.

The amount of congeners in the drink may also have an effect. Red wines have more congeners than white wines, and some people note less of a hangover with white wine.

In alcohol metabolism, one molecule of ethanol (the primary active ingredient in alcoholic beverages) produces 2 molecules of NADH, utilizing Vitamin B12 as a coenzyme. Over consumption of ethanol may cause vitamin B12 deficiency as well.

Some people believe that sugar (often found in sweet cocktails) worsens hangovers.

Nicotine poisoning can often worsen hangovers, as smokers tend to smoke much more than usual while under the influence of alcohol.

Genetics also plays a part, as some people seldom, if ever, suffer hangover symptoms no matter how much they drink.

The psychosomatic nature of hangovers shouldn't be ignored either. If people expect a hangover, they tend to feel one.

Answer 7

They are dehydrated...best cure for a hangover:

2 aspirin and a ton of water.

Answer 8

your body gets dehydrated. actually your killing cells because they do not have enough water. if you drink water while you are drinking alcohol, then you will not get a hangover.

Answer 9

DEHYDRATION. Drink lots of water before, during and after.

Answer 10

Depletion of vitamins. Take vitamins before drinking.