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As you age, your immune system – the body’s natural defence against infectious diseases – can start to deteriorate.

The importance of a strong immune system

A healthy immune system – made up of special organs, cells and chemicals – is needed to help fight infection from pathogens, protect against harmful substances in the environment and attack abnormal cells within our bodies (such as cancer cells). There are many ways in which the immune system offers protection, and these are generally grouped into two categories:

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Innate immune responses


Innate (non-specific) immune responses provide immediate defence against foreign pathogens or substances – these are the immune responses we are born with. Components of the innate immune system include physical barriers (e.g., skin, eyelashes, nose hair), chemical defenses (e.g., saliva, tears, stomach acid) and some types of white blood cells.

An icon of a virus

Adaptive immune responses


Adaptive or acquired immunity is not something we are born with – our bodies have to learn this response. The adaptive immune system must learn to identify and defend against foreign pathogens, meaning the initial response takes time. After first exposure, special immune cells "remember" pathogens, allowing faster and more accurate responses to future infections from the same pathogen.

The effects of ageing

As we grow older, our adaptive and innate immune systems can stop working as well as they used to. Some of the following changes may affect the immune system:

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  • Our immune system responds more slowly to pathogens or substances, increasing susceptibility to certain infectious diseases.
  • Immune cells reduce in numbers, which means our bodies may take longer to heal.
  • Our immune systems become less effective at detecting and correcting mutations in cells, which may increase our risk of cancer.
  • Autoimmune disorders may develop as the immune system becomes less able to distinguish self from non-self, increasing risk of damage to healthy cells.

Age-related decline in immune function may occur more rapidly after the age of 50. There are several other factors that can also contribute to decreasing immune system function, including genetics, environment, lifestyle and nutrition.

Making healthy lifestyle choices that strengthen and help protect your immune system can reduce your risk of infection, and also promote healthy ageing over the long term.

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Eat a balanced diet

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Stay active

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Keep up to date with immunisations

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Get adequate sleep

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Quit smoking and reduce alcohol intake

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Manage stress


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Diet and nutrition

A balanced and nutritious diet is essential for optimal functioning of all cells, including the cells of the immune system.

Eating for healthy immunity:

  • 1Take steps to avoid obesity. Obesity is associated with many health risks, including chronic inflammation, compromised immune function and increased risk of serious infection.
  • 2Ensure you are eating enough food. Undernutrition also compromises immune function by reducing the body's ability to fight off harmful pathogens.
  • 3Certain micronutrients, vitamins and antioxidants, are important to support a healthy immune system. Some foods that are rich in micronutrients include leafy greens, brightly coloured fruit and vegetables, and nuts and seeds.
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Active lifestyle

In addition to improving your overall health, regular moderate-to-vigorous exercise can enhance immune defence activity, reduce chronic inflammation and help slow age-related decline in immune system function.

Daily exercise recommendations:

  • Adults aged 50–64: aim for 2.5–5 hours of moderate intensity exercise, or 1.25–2.5 hours of intense exercise per week.
  • Adults aged 65+: try to get in 30 minutes of moderate intensity exercise most days.
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In addition to practicing good hygiene habits (e.g., regular hand washing, sneezing into a tissue), immunisation is another option that may help to protect against infectious diseases and also boost the immune system.

For more information, please speak to your healthcare professional. In the event of infection, early diagnosis and treatment by your doctor can sometimes hasten recovery and reduce the risk of complications.

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A good night’s sleep has a positive effect on immune health and long-lasting immune cell memory, reduces risk of infection, and improves infection outcome. On the other hand, long periods of sleep loss can lead to chronic inflammation and compromised immune function.

How much sleep do you need?




Adults aged 50–64 7–9 hours < 6 hours, or > 10 hours
Adults aged 65+ 7–8 hours < 5 hours, or > 9 hours

Adults aged 50–64


7–9 hours < 6 hours, or > 10 hours

Adults aged 65+


7–8 hours < 5 hours, or > 9 hours

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Smoking and alcohol

In addition to a myriad of other health risks, smoking and excessive alcohol consumption can trigger chronic inflammation, suppress immune function and increase risk of infection.

Did you know?

  • The immune system starts to recover within 3 months of quitting smoking.
  • In healthy adults, it is recommended to limit alcohol consumption to fewer than 10 standard drinks a week, and no more than 4 on any one day. Older adults with existing health issues should follow advice from their healthcare professionals. In general, the less you drink, the lower the risk of alcohol-related harm to the body.
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Stress management

Where short-term stress (minutes) helps prepare the body to fight infection, long-term stress (days to years) can accelerate ageing and immune dysfunction. The negative effects on ageing and the immune system largely result from chronic inflammation that leads to cell damage and reduced sensitivity to early signs of infection.

Although triggers are highly individual, there are several things you can do to help alleviate stress:

  • Stay connected with friends and family
  • Spend more time outdoors and exercising
  • Find a new hobby or creative outlet
  • Meditate
  • Eat well
  • Get enough sleep

NP-AU-NA-WCNT-210001 Date of GSK Approval: March 2021