Alcohol Absorption


How long will it take 72 oz. of 8% beer to clear the body?


It is important to note that in this question, an alcohol content of 8% has been specified. On average, domestic beers contain between 5-6% alcohol. In this situation, the alcohol content is higher, which may likely result in increased effects of alcohol being felt by the person consuming it.

 One serving of alcohol is fully absorbed into the blood stream within 30 minutes to 2 hours after intake. This is because the body can metabolize about 0.25 ounces of alcohol per hour. However, the effects of alcohol vary by individual and by how much alcohol they drink in one session. In fact, the effects and levels of alcohol in the body depend upon a number of factors:

•          a person’s size and weight

•          individual metabolism rate

•          related food intake

•          the beverage consumed

Generally speaking, alcohol is absorbed into the blood relatively quickly and metabolized more slowly. In an average 150 pound person, for example, each drink adds 0.02% to BAC and hour that passes removes 0.01% from it. This is why alcohol concentrations build steadily throughout a drinking session.


What is the the chief way for alcohol to be excreted?


The liver is responsible for the elimination - through metabolism - of 95% of ingested alcohol from the body. The remainder of the alcohol is eliminated through excretion of alcohol in breath, urine, sweat, feces, milk and saliva. The body uses several different metabolic pathways in its oxidation of alcohol to acetaldehyde to acetic acid to carbon dioxide and water.



How long does it take alcohol to be absorbed in your body?

Alcohol burns off at a precise rate of .016 BAC per hour, about equal to 1 standard drink each hour (depending on your weight). This rate is true regardless of the size of your body. A 5'2" female burns off alcohol at the same rate as a 6'1" obese male.

The differences, however, are in the rate with which your BAC rises. One drink in a small female of low weight constitutes a much larger percent of her BAC. It may take a male 5 drinks or more in an hour to reach a BAC of .08, while it may take a small female only 2 or three drinks.

Also, alcohol absorption varies depending on individual fat levels.  For instance, an individual with a lot of fat will be slower to absorb alcohol. However, when two people with equal weight, but different fat levels, drink the same amount of alcohol, the one with less fat will absorb the alcohol faster than the one with more fat while the absorption of alcohol metabolizes at the same rate.

Regardless of size or gender, the .016 metabolic rate is a constant. There is no way to speed up the process, whether you take an enzyme test, drink coffee, take cold showers or vomit. About 10% of alcohol leaves the body in breath, sweat and urine, but most is broken down by the liver which takes an hour per standard drink. Essentially it takes time to get rid of the alcohol from your body. The chart below illustrates the length of time it will take for your body to get rid of the alcohol in your system.

 BAC Level

Hours Until 0





 .08(legal limit)




 .16(2x legal)




 .24(3x legal)


How does alcohol travel through our bodies?


Alcohol is metabolized extremely quickly by the body.  Unlike foods, which require time for digestion, alcohol needs no digestion and is quickly absorbed.   Alcohol gets VIP treatment in the body absorbing and metabolizing before most other nutrients.  About 20 percent is absorbed directly across the walls of an empty stomach and can reach the brain within one minute.

Alcohol is rapidly absorbed in the upper portion of the small intestine. The alcohol-laden blood then travels to the liver via the veins and capillaries of the digestive tract, which affects nearly every liver cell.  The liver cells are the only cells in our body that can produce enough of the enzyme alcohol dehydrogenase to oxidize alcohol at an appreciable rate. 

Though alcohol affects every organ of the body, it’s most dramatic impact is upon the liver.  The liver cells normally prefer fatty acids as fuel, and package excess fatty acids as triglycerides, which they then route to other tissues of the body.  However, when alcohol is present, the liver cells are forced to first metabolize the alcohol, letting the fatty acids accumulate, sometimes in huge amounts.  Alcohol metabolism permanently changes liver cell structure, which impairs the liver’s ability to metabolize fats.  This explains why heavy drinkers tend to develop fatty livers.

The liver is able to metabolize about ½ ounce of ethanol per hour (approximately one drink, depending on a person’s body size, food intake, etc.).  If more alcohol arrives in the liver than the enzymes can handle, the excess alcohol travels to all parts of the body, circulating until the liver enzymes are finally able to process it.

With moderate drinking, the liver can process alcohol fairly safely.  However, heavy drinking overtaxes the liver resulting in serious consequences.  A liver clogged with fat causes liver cells to become less efficient at performing their necessary tasks, resulting in impairment of a person’s nutritional health.  Fatty liver is the first stage of liver deterioration in heavy drinkers, and interferes with the distribution of oxygen and nutrients to the liver’s cells.  If the condition persists long enough, the liver cells will die, forming fibrous scar tissue (the second stage of liver deterioration, or fibrosis).  Some liver cells can regenerate with good nutrition and abstinence, however in the last stage of deterioration, or cirrhosis, the damage to the liver cells is the least reversible.


What are some of those other factors that could impact your level of drunkenness?  Are you referring to gender and weight?

Yes, gender and weight are two common examples of factors that impact someone’s blood alcohol content (BAC).  Women produce less of the alcohol metabolizing enzymes in the body which means it takes a woman longer to break down the alcohol than it would a man of the same size.  When discussing weight, it is important to think of body mass index rather than weight alone. Not only heavier but more muscular individuals have more blood to dilute the alcohol, resulting in lower blood alcohol content levels. 

Some other factors include what is in your stomach.  If you drink on an empty stomach, there is nothing there to slow the rate of absorption and can lead to a higher BAC level.  Lack of sleep can cause a higher BAC since your liver does not work as well when you are tired.  If you are sick you might be dehydrated which adds to the effects of alcohol.  Mixing alcohol with other drugs can have dangerous impacts of the effects alcohol has on the body and I don’t just mean illegal drugs.  Doctor prescribed or over the counter medications must be used carefully when combined with alcohol.  Every person is different and will react to alcohol differently.  It is important to know yourself and your limits. 


How long does date rape drugs remain in your blood?


The length of time that the effects of date rape drugs last varies. It depends on how much of the drug is taken and if the drug is mixed with other substances, like alcohol. Alcohol can worsen the drug's effects and can cause more health problems.



I heard that alcohols need 3 months to get out totally of our system, is that true? Where is is stocked if its not in our blood anymore? Does it modify our DNA ?


Approximately 10% of the total amount of alcohol consumed is expelled out of your body via sweat, breath and urine. The rest of the alcohol consumes is broken down into by products through the phenomenon of metabolism within our body. Alcohol is metabolized at the rate of .015 of blood alcohol concentration (BAC) every hour.


When alcohol is metabolized in the human body, it is converted to acetaldehyde, a chemical that is structurally similar to formaldehyde. Acetaldehyde can cause DNA damage, trigger chromosomal abnormalities in cell culture studies, and act as an animal carcinogen.



How long after an individual stops drinking does alcohol continue to be absorbed into the bloodstream?


When a person drinks an alcoholic beverage, about 20 percent of the alcohol is absorbed in the stomach and about 80 percent is absorbed in the small intestine. How fast the alcohol is absorbed depends upon several things:

  • The concentration of alcohol in the beverage - The greater the concentration, the faster the absorption.
  • The type of drink - Carbonated beverages tend to speed up the absorption of alcohol.
  • Whether the stomach is full or empty - Food slows down alcohol absorption.

After absorption, the alcohol enters the bloodstream and dissolves in the water of the blood. The blood carries the alcohol throughout the body. The alcohol from the blood then enters and dissolves in the water inside each tissue of the body (except fat tissue, as alcohol cannot dissolve in fat). Once inside the tissues, alcohol exerts its effects on the body. The observed effects depend directly on the blood alcohol concentration (BAC), which is related to the amount of alcohol consumed. The BAC can rise significantly within 20 minutes after having a drink.


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