We’re all familiar with the visible signs of ageing, such as changes to our skin, greying hair, and reduced muscle mass. But we may not think as often about the internal changes associated with ageing. To make sense of these changes, it’s important to understand what happens to our bodies as we age.
Ageing is a complex process, but generally refers to a decline in physical and mental functioning—usually due to a gradual build-up of damage to cells, tissues, and organs—that may increase the risk of disease over time. As we age, our immune system function, and the mechanisms that help protect us from infections and disease, can start to decline.
Understanding the human immune system
We live in a world full of bacteria, viruses, and other disease-causing microorganisms. Our bodies are under constant threat from these foreign pathogens. If left to their own devices, these pathogens can inflict damage to our cells and organs—the basis of disease. So, how do we defend against these tiny invaders?
The human immune system is designed to help prevent and fight infection and disease. It helps fight foreign pathogens, protect against harmful substances in the environment (such as toxic pollutants and allergens), and detect abnormal, potentially cancerous, cells. This is made possible by a complex network of specialised cells, organs and chemicals that regulate immune responses.
How ageing affects the immune system
By middle age, a decline in the number and function of specialised cells within the immune system may become more prominent. Below are some (not all) of the age-related changes that may occur:
- Production (formation of new cells) and proliferation (replication of existing cells) of some types of immune cells may slow.
- Some cells may not move to sites of infection as efficiently as they used to.
- Some cells may start to struggle to recognise foreign pathogens (such as bacteria and viruses) and detect abnormal cells.
Changes to the body and immune system may lead to chronic inflammation, impaired wound healing, diminished response to infectious pathogens and an increased risk of some cancers.
What influences the rate the immune system ages?
When it comes to ageing, one size certainly does not fit all. Some people keep a high level of immune system functioning well into their senior years. In contrast, other people start to show signs of ageing much earlier. The rate of ageing can be influenced by several factors, such as genetic differences (inherited traits), personal characteristics (e.g., sex and lifestyle choices) and social environment.
Maintaining healthy behaviours throughout life can help support immune system function and reduce the risk of infection. Some examples of behaviours that might benefit the immune system include:
- getting enough quality sleep
- managing stress
- eating a balanced diet
- staying active
- avoiding tobacco and excessive alcohol consumption
- keeping up to date with health checks and immunisation status reviews
The above information is not intended to substitute for professional medical advice and should not be relied on as health or personal advice.
NP-AU-NA-WCNT-210008 Date of GSK Approval: June 2021
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