Alcohol & The Immune System: Does Drinking Lower Your Immune System?

Written by Melissa Carmona

& Medically Reviewed by Benjamin Caleb Williams, RN

Medically Reviewed

Last updated: 12/24/2020

This article was reviewed by a medical professional to guarantee the delivery of accurate and up-to- date information. View our research policy.

Editorial Policy

Medically Reviewed by Benjamin Caleb Williams, RN

View our editorial policy
If you or a loved one is struggling with addiction, help is available. Speak with a Recovery Advocate by calling (561) 340-7269 now.


Learn about how alcohol affects your immune system and what you can do about it.

While people who drink alcohol should always be aware of alcohol’s effects on their immune systems, the recent pandemic has made this awareness even more important. Alcohol does suppress people’s immune systems; it does not have to be used for long periods of time to make you more susceptible to infections.

Infections occur when a virus or bacteria invades the body and multiplies, producing more and more of itself. The immune system is a complicated group of cells and proteins that recognize invading bacteria or viruses and destroy these infections. Alcohol disrupts the immune system and makes people more likely to develop an infection.

Levels of Alcohol Consumption

There are three different levels of alcohol consumption that physicians often refer to. These are light drinking, moderate drinking and heavy drinking. The differences between these terms vary based on gender. Women cannot metabolize alcohol as quickly as men, so a smaller amount of alcohol can lead to a higher amount in a woman’s bloodstream. According to the National Institute on Alcohol Abuse and Alcoholism (NIAAA), the drinking levels are defined as:

  • Light drinking: Less than one drink per day for women or less than two drinks per day for men.
  • Moderate drinking: 1–3 drinks per day for women or 2–4 drinks per day for men.
  • Heavy drinking: More than three drinks per day for women or more than four drinks per day for men.

NIAAA also includes a category for binge drinking — drinking a very large amount of alcohol in a short amount of time. While the actual definition is based on an individual’s change in blood alcohol levels, the NIAAA states that, in an average adult, drinking four or more drinks for women or five or more for men in two hours will typically be considered binge drinking.

How Does Alcohol Affect the Immune System?

Alcohol can affect the immune system in many ways, some of which are still the topic of research. While it has been known for some time that alcohol use can make people more prone to infections, recent research has helped medical professionals better understand how this happens.

Alcohol is known to disrupt the body’s microbiome. The microbiome is the bacteria that naturally live on our skin, in our digestive tract and in part of the reproductive system in females. These bacteria are necessary for optimal health, and their presence helps prevent harmful bacteria from having the space needed to grow. By disrupting this microbiome, alcohol makes infection more likely to occur.

Alcohol also affects the cells that fight against infection and the inflammatory response. By affecting the complicated balance of the immune system and how it functions, alcohol can make infections more likely to occur and last longer.

Short Term Effects of Alcohol On the Immune System

When people think about the negative health effects of alcohol use, they tend to picture someone who has been drinking copious amounts of alcohol for years. Unfortunately, the effects of alcohol on the immune system can affect a much wider range of people.

While chronic alcohol use is certainly quite harmful to the immune system, one recent study found “even a single episode of binge drinking can have measurable effects on the innate immune system.” The NIAAA warns that getting drunk can make your body’s immune system slower for up to 24 hours after the last drink.

Long Term Effects of Alcohol On the Immune System

While short-term alcohol use can be harmful to the immune system, chronic alcohol use can be even more devastating. Chronic alcohol exposure can:

  • Interfere with how the immune system responds and adapts to bacteria
  • Make you more likely to get viral and bacterial infections
  • Increase inflammation, even in the absence of an infection

How Much Alcohol Lowers the Immune System?

The amount of alcohol needed to lower the immune system varies significantly between individuals. Many factors besides the amount and duration of alcohol use influence how alcohol affects the immune system. These factors may include:

  • Age
  • Gender
  • Overall health
  • History of infections
  • History of immune system problems
  • Genetic factors

While the amount of alcohol used and the effect on the immune system will vary for everyone, even a single episode of alcohol use can create a measurable effect. The question is not how much alcohol it will take to cause an effect, but how great the effect will be.

Alcohol-Related Diseases

While alcohol can significantly affect the immune system, many alcohol-related diseases can affect other parts of your body. Most alcohol-related diseases are more likely to occur in someone who has been using alcohol chronically. However, any alcohol use starts to raise your risk of an alcohol-related disease.

Alcohol-related diseases are numerous. According to the U.S. Centers for Disease Control and Prevention (CDC), some of the health problems created by alcohol use include:

  • High blood pressure
  • Heart disease
  • Stroke
  • Liver disease
  • Digestive problems
  • Many types of cancers
  • Weakened immune system
  • Learning and memory problems
  • Dementia
  • Alcohol use disorder

Alcohol and Lung Disease

Alcohol’s immune system suppression can be particularly harmful to the lungs. Pneumonia, for example, is an infection in the lungs. The body fights off this infection by flooding the lungs with fluid containing immune cells. While necessary to fight the infection, the immune response can essentially cause someone to drown as they fight the infection.

Alcohol use, even single episodes, increases the risk of pneumonia by suppressing the immune system and allowing infection opportunities to take hold. Alcohol can also make pneumonia last longer by allowing the bacteria more time to multiply and inhibiting the body’s ability to fight back.

A specific type of pneumonia, called aspiration pneumonia, occurs when someone accidentally breathes in food or fluid that contains bacteria. Alcohol makes people vomit, and it is very easy to accidentally inhale some of this vomit. Vomit that is inhaled into the lungs often contains bacteria. When combined with a suppressed immune system, this can be the perfect storm for a bad case of pneumonia.

Alcohol Abuse and COVID-19

During the COVID-19 pandemic, more and more people are facing isolation, fear, anxiety and stress. Alcohol use and misuse have increased during these difficult times, putting more people at risk for alcohol use disorder and a lowered immune system.

While the research on this disease is still very new, it is well understood that this infection can be fatal and that those with a lowered immune system can be more at risk. More importantly, one of the respiratory complications associated with moderate-to-BLu1mAsevere COVID-19 is pneumonia.

Video about a medical complications cause by extended alcohol use.

Repairing the Immune System After Alcohol Use

There are several steps you can take to promote your immune system health and avoid further damage to your immune system. These include:

  • Avoiding smoking
  • Following a diet that is high in fruits and vegetables
  • Getting sufficient sleep
  • Exercising regularly
  • Maintaining a healthy weight
  • Reducing stress when possible
  • Following good hygiene
  • Following local infection control guidelines

While it is impossible to fully prevent getting an infection, taking steps to improve your immune health will give your body the best chance of quickly fighting potential infections.

Finding Help for Alcohol Addiction

Alcohol addiction can occur slowly and incrementally, making it difficult for someone to realize they have it. If you know someone who is finding it difficult to stop or control their drinking, professional help is available. Stopping alcohol use and promoting optimal immune health is particularly important during this pandemic.

The Recovery Village at Baptist Health helps people recover from alcohol addiction with evidence-based treatment and compassionate care. Reach out to our team to learn more about addiction treatment options that can help you on the path to recovery.

View Sources

Abel, E.; Kruger, M.; & Friedl, J. “How do physicians define “light,” “moderate,” and “heavy” drinking?” Alcoholism: Clinical and Experimental Research. 1998. Accessed October 23, 2020.

National Institute on Alcohol Abuse and Alcoholism. “Drinking Levels Defined.” 2020. Accessed October 23, 2020.

Szabo, Gyongyi & Saha, Banishree. “Alcohol’s Effect on Host Defense.” Alcohol Research: Current Reviews. 2015. Accessed October 23, 2020.

National Institute on Alcohol Abuse and Alcoholism. “Alcohol’s Effects on the Body.” 2020. Accessed October 23, 2020.

US Centers for Disease Control and Prevention. “Alcohol Use and Your Health.” October 1, 2020. Accessed October 23, 2020.

Kershaw, Corey & Guidot, David. “Alcoholic Lung Disease.” 2008. Accessed October 23, 2020.

Harvard Health Publishing. “How to boost your immune system.” April 6, 2020. Accessed October 23, 2020.

Simpson, J. Cavanaugh. “Hold the “Quarantinis”: Alcohol and Novel Coronavirus Might Not Mix.” Johns Hopkins Bloomberg School of Public Health. March 19, 2020. Accessed October 23, 2020.

Authorship