Drink, drank or drunk – whatever state of imbibing you’re in, the way you metabolize alcohol has an impact. From genes that affect alcohol metabolism from that first sip of wine to metabolic processes that contribute to that nasty hangover, alcohol’s journey through your body is complex.

When you drink alcohol, you lose 2 to 8% through sweat, saliva, breath and urine. Here’s what happens to the other 92 to 98% of it:

  1. Alcohol moves through the digestive system and is absorbed into the bloodstream, brain, stomach and small intestines.
  2. Your brain ups the amount of dopamine, its feel-good chemical, and GABA, its inhibitory neurotransmitter, all the while decreasing glutamate, the excitatory neurotransmitter. These changes make you feel buzzed and relaxed. Too much alcohol and these effects intensify from a pleasant buzz to less desirable traits like slurred speech, clumsiness, slower reaction times and intense emotions.
  3. The liver takes center stage for alcohol metabolism. It does most of the heavy lifting tied to breaking down alcohol so it can be excreted from the body. The primary enzymes that help “break apart” alcohol are:
  • Alcohol dehydrogenase (ADH) – This enzyme metabolizes alcohol to acetaldehyde, a highly toxic substance and carcinogen.
  • Aldehyde dehydrogenase (ALDH) – The ALDH enzyme breaks acetaldehyde down into a less toxic substance, acetate, which is further metabolized by other enzymes into water and carbon dioxide so the body can eliminate it.

How Long Does Alcohol Metabolism Take?

As a rule of thumb, it takes about one hour for your body to metabolize one ounce of alcohol. However, the time alcohol metabolism takes is also impacted by these factors:


The amount of metabolizing enzymes in the liver varies between people. If you have fewer “alcohol enzymes,” it will take longer to metabolize alcohol.


As you age, less body water and slower alcohol metabolism increases your sensitivity to alcohol, keeping larger amounts of it in your system longer (especially if you’re 65 or older).


Alcohol’s intoxicating effect decreases as weight increases, i.e., smaller people get drunk faster than those who have more meat on their bones.


Women may get buzzed off less alcohol than men. That’s because women have less of the ADH enzyme, are usually smaller and have less water in their bodies than men, so alcohol stays in their system longer.


The longer the time between drinks, the lower your blood alcohol content (BAC) will remain. More time between drinks gives the liver longer to metabolize alcohol.


Certain medications can interfere with alcohol metabolism, essentially “competing for attention” from the same enzymes involved in metabolizing processes. These include some types of analgesics (pain medications), antidepressants and antibiotics.

Food Intake

Contrary to popular belief, food doesn’t “soak up” alcohol, keeping you from getting drunk faster. In reality, ADH enzymes are higher when you have food in your stomach and food can also increase liver blood flow. Both of these conditions aid in quicker alcohol metabolism.

Your blood alcohol concentration (BAC) is typically at its highest between 30 to 45 minutes after consuming one standard drink. A standard drink is defined as 5 ounces of wine, 1.5 ounces of 80-proof distilled liquor or 12 ounces of beer.

Do Genes Affect Alcohol Metabolism?

Genetics can affect the ADH and ALDH enzymes in different ways. For example, genes can cause different forms of enzymes, which can impact alcohol metabolism in ways like processing it at faster and slower rates. This is similar to the way genes can impact the rates of antidepressant metabolism.

The two most studied of these alcohol gene variations include:

Beta3 Class I ADH Isoforms

Some ethnic groups such as Native Americans may carry a certain form of ADH (beta3 class I ADH isoforms) that cause them to eliminate alcohol at a higher rate than those without this form.

Alcohol Flush Reaction

A condition called alcohol flush reaction occurs in about 36% of people of Asian descent. It causes their skin to appear blotchy and red, and happens when they metabolize alcohol too quickly and have too little of the ALDH enzyme. This results in an excess of acetaldehyde, a toxic byproduct of alcohol.

How Does Alcohol Metabolism Contribute to Hangovers?

Many factors go into creating a hangover, including the way alcohol is metabolized. When alcohol is processed in the liver, it’s first converted into acetaldehyde, a very toxic substance. Luckily, the next

step in alcohol metabolism is to break acetaldehyde into a less toxic form and excrete it from the body. However, if you’re drinking alcohol more quickly than your body can metabolize it, you’re going to end up having large amounts of this toxin in your system for longer periods of time, which isn’t good for anyone. Large amounts of acetaldehyde can lead to vomiting and headaches. Other reasons for hangover symptoms include dehydration, excess stomach acid, low blood sugar, expanded blood vessels and sleep disturbances.

Alcohol Metabolism and Disease

Regularly consuming large amounts of alcohol can lead to excessive amounts of toxic byproducts given off during alcohol metabolism. This puts you at greater risk for a number of cancers like:

  • Upper respiratory tract cancers
  • Liver cancer
  • Colon and rectum cancer
  • Breast cancer

Some people are less affected by carcinogens than others. Researchers theorize it has something to do with having certain genes that offer a “protective factor.” Some heavy drinkers never develop alcohol-related cancers while some moderate drinkers do. Science is still trying to sort out these details. In the meantime, why risk it? If you’re rolling the dice, drinking more than you should and hoping you have “the right genes” so you avoid potential health consequences, it might be time to take a closer look at your drinking patterns.


Choose a better life. Choose recovery.