Understanding alcohol and our immune system

Our immune system helps keep us healthy.

But drinking can weaken this system, leaving us vulnerable to infections and diseases.

How our immune systems work

The white blood cells, tissues and organs that make up our body’s immune system are designed to fight off infections, disease and toxins.

The immune system is made up of two parts:

• the innate immune system: this provides general immunity by responding to viruses, bacteria and other microorganisms that can cause disease
• the adaptive immune system: this looks after your immune memory. This includes things like remembering what a previous infection looked like, such as chickenpox, and stopping it from happening a second time.¹

Drinking has a negative impact on both parts of the immune system.²

There’s no ‘safe’ level of drinking. It has short and long-term effects on every organ in the body.³

Short-term effects of alcohol on the immune system

You don’t have to be a regular heavy drinker for alcohol to affect the immune system. Drinking 5-6 drinks in a single session can suppress the immune system for up to 24-hours.^{4, 5}

Long-term effects of alcohol on the immune system

Over time, drinking can lead to longer term problems because the immune system takes longer to recognise and respond to infections.³

Some longer-term effects include:

• more intense illnesses
• symptoms lasting longer
• the immune system having to work harder to fight off the infection.³

How alcohol impacts the lungs

Our lungs are particularly vulnerable to the effects of alcohol.

Excessive drinking can impact the immune cells that protect the lungs. Alcohol can also impact the cells within the airways, reducing their ability to remove mucous from the lungs. This can damage the lung tissue and lead to a weakening of lung function over time.^5-7

This weakening often goes unnoticed until severe infection occurs.

Heavy drinking can result in a 3-7 times higher vulnerability to serious conditions, like pneumonia, developing from common respiratory tract infections.^5-7

How alcohol impacts the gut

We need lots of different ‘good’ bacteria in our gastrointestinal (GI) tract for healthy immune function.

Alcohol can impact both the number and variety of these bacteria, worsening our immune system.⁸

The cells that make up the lining of the GI tract regulate what’s absorbed into our bodies. Alcohol impacts these cells. This is one of the factors linked to the development of alcohol liver disease.⁸

Protecting our health

You can lower the risk of alcohol impacting your immune system by drinking less.

To reduce your risk, it’s recommended that Australians drink no more than 10 standard drinks per week, and no more than 4 on any one occasion.⁹

If you’re curious or concerned about how much alcohol you’re consuming, you can use the online drinking calculator or call the National Alcohol and Other Drug Hotline on 1800 250 015 for information.

Tips and more info

• Looking to cut down on alcohol? There are strategies you can start using to drink less.
• The weekend is often a time we are most likely to drink. Check out these tips on how to drink less on weekends or holidays.
• The alcohol industry frequently tries to downplay the health risks linked to drinking. Find out more in part one of our two-part series about tactics used by the alcohol industry to undermine public health.