Your immune system helps protect your body from foreign or harmful substances. Examples are bacteria, viruses, toxins, cancer cells, and blood or tissues from another person. The immune system makes cells and antibodies that destroy these harmful substances.

AGING CHANGES AND THEIR EFFECTS ON THE IMMUNE SYSTEM

As you grow older, your immune system does not work as well. The following immune system changes may occur:

• The immune system becomes slower to respond. This increases your risk of getting sick. Flu shots or other vaccines may not work as well or protect you for as long as expected.
• An autoimmune disorder may develop. This is a disease in which the immune system mistakenly attacks and damages or destroys healthy body tissues.
• Your body may heal more slowly. There are fewer immune cells in the body to bring about healing.
• The immune system's ability to detect and correct cell defects also declines. This can result in an increased risk of cancer.

PREVENTION

To decrease the risks from immune system aging:

• Get vaccines to prevent the flu, COVID-19, shingles, and pneumococcal infections, as well as any other vaccines your health care provider recommends.
• Get plenty of exercise. Exercise helps boost your immune system.
• Eat healthy foods. Good nutrition keeps your immune system strong.
• Do not smoke. Smoking weakens your immune system.
• Limit your intake of alcohol. Ask your provider how much alcohol is safe for you.
• Look into safety measures to prevent falls and injuries. A weak immune system can slow healing from injuries.

OTHER CHANGES

As you grow older, you will have other changes, including in your:

• Hormone production
• Organs, tissues, and cells