Alcohol and Liver Effects: What’s Reversible vs. Permanent?
Medically reviewed by Kashif J. Piracha, MD
Alcohol can damage the liver if consumed in excess. While the liver can often repair itself after a period of alcohol use, the chronic, heavy consumption of alcohol can lead to permanent damage and the onset of cirrhosis, in which the liver is less able to filter blood. This, in turn, increases the risk of liver failure and liver cancer.
This article looks at the short-term and long-term effects of alcohol on the liver and what happens if you drink alcohol occasionally, daily, or heavily. It also explains the consequences of heavy drinking and whether it's possible to recover from liver damage after heavy alcohol use.
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Alcohol and Liver Effects
The liver is an organ about the size of a football in the average healthy adult. It has many functions in the human body, including:
Filtering toxins from the bloodstream
Regulating blood sugar (glucose) levels
Regulating blood cholesterol levels
Aiding in the digestion of food
Helping fight infection and disease
Every time you drink alcohol, some liver cells (called hepatocytes) die. Although the liver is a robust organ that can regenerate new liver cells, drinking too much over many years can reduce its ability to regenerate cells.
The effects of alcohol on the liver can change with short-term and long-term use.
Short-Term Use
When alcohol enters the bloodstream, it is metabolized (broken down) by the liver into a toxic chemical called acetaldehyde, which is further metabolized to acetate. Acetate is then broken down to water and carbon dioxide, which are eliminated from the body.
Acetaldehyde can damage the liver. Acetaldehyde is a highly reactive, toxic chemical that the immune system recognizes as harmful. The binding of acetaldehyde to proteins and fat cells in the liver triggers an inflammatory response that can damage and kill hepatocytes.
The breakdown of alcohol also leads to the production of reactive oxygen species (ROS). These are highly unstable molecules that can turn on and off certain functions in the body. In the liver, ROS affects how fat cells are produced, triggering the accumulation of fat known as hepatic steatosis or fatty liver disease.
If the liver is healthy, fatty liver disease can be reversed, and hepatocytes can start to regenerate themselves over a relatively short period. However, with ongoing use, these capabilities can be impaired, sometimes irreversibly.
Related: Lifestyle Tips for Fatty Liver Disease
Long-Term
Long-term alcohol use can lead to the progression of liver disease and the development of scar tissues, known as fibrosis. During early-stage liver disease, fibrosis is often reversible if alcohol use is permanently stopped.
However, when scarring is severe enough to impair the function of your liver, you are said to have cirrhosis. Cirrhosis is typically progressive and irreversible.
If you have cirrhosis and the liver is still relatively functional, you are said to have compensated cirrhosis and not experience any notable symptoms.
If the damage is so extensive that the liver is no longer able to service the body's needs, you are said to have decompensated cirrhosis, which leads to liver failure.
Related: How Alcohol Affects Different Parts of the Body
Quantity of Alcohol and Liver Function
The amount of alcohol you consume, along with how long you drink, influences your risk of fatty liver disease, fibrosis, and cirrhosis.
Risk is also influenced by the type of beverage you drink since alcohol content varies by type. While beer, for example, contains about 4% or 5% alcohol, wine contains around 12% and distilled spirits around 40%.
According to the National Institute of Alcohol Abuse and Alcoholism, a "standard" drink contains about 0.6 fluid ounces, or 14 grams (g), of pure alcohol. Beverages differ in their percentages of pure alcohol. Therefore, a standard drink is the following amounts per beverage type:
12 fluid ounces of beer
8 to 10 fluid ounces of hard seltzer
5 fluid ounces of table wine
3 to 4 fluid ounces of fortified wine (like port or sherry)
2 to 3 fluid ounces of cordials or aperitifs (like Cointreau)
1.5 fluid ounces of distilled spirits (such as vodka, whiskey, rum, gin) or brandies
Occasional Consumption
Although the liver is efficient in metabolizing small quantities of alcohol and regenerating new liver cells, drinking a large amount, even for a few days, can lead to fatty liver disease. The condition is usually asymptomatic (without symptoms) and, if you stop drinking for two weeks, is fully reversible.
The same may not be true if you binge drink. Binge drinking is defined as drinking more than four standard drinks for women or more than five standard drinks for men on a single occasion.
Extreme binge drinking can sometimes lead to acute pancreatitis and, in severe cases, alcohol poisoning. There is evidence that even occasional bouts of binge drinking have led to permanent liver damage.
A 2017 animal study conducted by the University of California at San Francisco reported that it only took 21 binge-drinking sessions in mice to induce symptoms of early-stage liver disease.
The results suggest that relatively short periods of excessive drinking can lead to liver damage. It remains unclear whether these changes to the liver are completely reversible.
A Note on Gender and Sex Terminology
Verywell Health acknowledges that sex and gender are related concepts, but they are not the same. To reflect our sources accurately, this article uses terms like “female,” “male,” “woman,” and “man” in the same way the sources use them.
Daily Consumption
According to the 2020–2025 Dietary Guidelines for Americans, moderate alcohol use is defined as up to one standard drink per day for women or two standard drinks a day for men.
These amounts have long been considered "safe" for the liver. However, when the intake is increased to over 30 g per day in men and 20 g in women, there is not only an increased risk of fibrosis but also an increased risk of progression to cirrhosis.
Other factors may contribute to the onset of cirrhosis with daily alcohol use. According to the long-standing Million Women Study conducted in the United Kingdom, drinking alcohol on an empty stomach increases the risk of cirrhosis compared to drinking alcohol with food. Consuming distilled spirits was also seen to increase the risk compared to drinking wine only.
As such, your risk of liver disease is influenced not only by how much you drink and what you drink but also by how you drink alcohol.
Heavy Consumption
Heavy alcohol use is defined as eight or more drinks per week for women or 15 or more drinks per week for men. Others define it as binge drinking five or more days in the past month.
Studies have shown that consumption levels this high almost invariably place you at risk of liver disease. According to the European Association for the Study of the Liver, the risk increases when over 140 g of alcohol are consumed per week by women and more than 210 g are consumed per week by men.
Moreover, when more than 60 g of alcohol are consumed per day, the risk of cirrhosis-related death increases by 14 times in men and 22.5 times in women compared to nondrinkers.
Why Are Females at Greater Risk?
Females are at greater risk of alcohol-related liver disease in part because they produce less aldehyde dehydrogenase (ALDH), the enzyme that breaks down acetaldehyde. As a result, liver cells are exposed to the damaging effects of acetaldehyde for far longer. Estrogen appears to play a key role in why ADHL levels are lower in females.
Liver Damage vs. Liver Failure From Alcohol
Decompensated cirrhosis occurs when severe scarring makes the liver incapable of filtering blood or performing other essential body functions. As opposed to compensated cirrhosis, in which you may not feel or look sick even if the liver is severely scarred, decompensated cirrhosis will invariably cause symptoms.
Symptoms of alcohol-related liver failure tend to develop rapidly, causing:
Upper abdominal tenderness or pain
Persistent tiredness and weakness
Nausea
Fever
Poor appetite
Yellowing of the skin and eyes (jaundice)
Accumulation of fluid in the abdomen (ascites)
Vomiting blood or coffee-ground-like clots (hematemesis) or blood in the stools
As liver failure progresses, rising toxin levels can start to affect the brain, leading to hepatic encephalopathy. This can cause mood or personality changes, impaired thinking, loss of concentration, and sleep problems. In severe cases, coma can occur.
With progression, liver failure can lead to hepatorenal syndrome (HRS) in which the kidneys also start to fail. HRS is a life-threatening complication. Around 50% of people die within two weeks of diagnosis, and 80% die within three months.
Related: Complications of Cirrhosis You May Not Know
Cancer, Alcohol, and Liver
Alcohol-related liver disease puts you at risk of liver cancer. While the cause is not entirely known, the production of reactive oxygen species created by the breakdown of alcohol is known to damage the DNA of many cells in the body, including liver cells. Over time, this can cause hepatocytes to replicate abnormally, resulting in liver cancer.
Acetaldehyde is classified as a probable human carcinogen (cancer-causing agent).
According to the National Cancer Institute, heavy alcohol consumption is associated with a twofold increased risk of hepatocellular carcinoma (the most common type of liver cancer) and intrahepatic cholangiocarcinoma (a related cancer affecting the bile ducts).
The risk of liver cancer from alcohol use appears to be dose-dependent, meaning that your risk increases with the amount you drink.
According to a 2015 analysis in the peer-reviewed journal Cancer Causes & Control, consuming 12 grams of pure alcohol per day (a little less than what's considered one standard drink) increases the risk of liver cancer risk by 8%. The risk increases to 54% when 50 g are consumed and 320% when 100 g are consumed.
Recovering From the Effects of Alcohol on the Liver
There is no specific treatment for alcohol-related liver disease other than to stop drinking, preferably for the rest of your life. This reduces the risk of further liver injury, giving you the best chance of recovering.
Early-stage liver disease is fully reversible once alcohol is stopped. However, if there is progression from fibrosis to cirrhosis, the odds of regression (reversibility) are decreased. But that doesn't necessarily mean that you are destined to get worse.
Even if cirrhosis can’t be fully reversed, stopping alcohol can greatly reduce its severity, increasing blood circulation and improving the regeneration of hepatocytes. Healthcare providers can measure this with a type of ultrasound called a FibroScan and a panel of blood tests called liver function tests (LFTs).
A 2021 review of studies in the journal Alcohol Research reported that one month of abstinence can return LFTs to normal levels even in people who previously consumed 258 g of alcohol per week. While this may not reverse cirrhosis, it can go a long way toward slowing disease progression and reducing the risk of liver cancer or liver failure.
Moderation or Abstinence?
If you have fatty liver disease, it may be reasonable to drink in moderation once any damage to the liver has been reversed. Your healthcare provider can tell you when it is safe to do so.
On the other hand, if you have been diagnosed with cirrhosis or develop symptoms of hepatitis, lifelong abstinence is advised.
Related: How to Stop Drinking If You Can't
Summary
Alcohol can damage the liver. While the liver has the remarkable ability to regenerate itself after alcohol use, ongoing heavy consumption can lead to scarring that reduces liver function and can also permanently damage the liver.
Limiting your intake to one standard drink per day if you are female and two standard drinks if you are male is generally considered "safe" for your liver. However, even occasional binge drinking can lead to liver damage if enough is consumed.
If alcohol use leads to cirrhosis, the only way to prevent progression (and reduce the risk of liver cancer or failure) is to quit.
Read Next: What Happens If You Stop Drinking for One Month
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