Alternative Names immune system changes associated with ageing, age-related changes in immunity, age-related changes in the immune system
Definition The immune system's job is to seek out and destroy invaders that can harm the body. Normal changes in the immune system occur with age.
What is the information for this topic? The main job of the immune system is to fight off infections. It also plays a role in helping to stop cancer in the body. The function of the immune system declines with age. This does not mean that people get sick more often. But, as people get older, the risk of illness does increase.
With age, the number of immune cells may decrease slightly. More importantly, the function of these cells decreases. The cells are often less able to control illness than in earlier years. Certain cells in the immune system make proteins called antibodies to fight off infections. As people age, their immune system produces a smaller amount of antibodies. This means that vaccines such as flu Injections may provide less protection in older people.
Cells of the immune system can also lose their ability to tell the difference between normal and abnormal tissue. When this occurs, it can lead to autoimmune disease. This describes a condition in which the immune system attacks a person's own body. This change also means that the ability to identify and fight cancer is decreased. This is thought to be one reason that the risk of many cancers increases with age. Other body changes allow more bacteria to enter the body. For example, ageing skin provides less protection against bacteria than younger skin. If the immune system worked well, this would not be a big problem. However, because of the age-related weakness in the immune system, these other changes can also increase the risk of infections.
To minimise the risk of infection and cancer, people should:
keep vaccines up to date. For example, a pneumovax vaccine can help prevent pneumonia. A flu Injection is advised every year and a tetanus Injection is advised every 10 years. People should see a doctor about the most up-to-date schedule for adult vaccines.
implement home safety measures to reduce the chance of injury, which can lead to infection.
Author: James Broomfield, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
