The immune system protects your body from bacteria, viruses and substances that don’t belong there (like a splinter). These are called antigens. When an antigen enters your body, it triggers a series of responses to fight or destroy it. Some of these are cellular, such as T cells or B cells. Others are enzymatic, such as phagocytes that eat or destroy harmful microorganisms. Antibodies are proteins that bind to antigens, like lock and key. Once they attach to an antigen, phagocytes kill the germ or signal other immune cells to attack it.
Innate immunity is protection you are born with, and it is active from the moment you are born. This is also called natural immunity or passive immunity.
Acquired immunity is protection you gain over time, usually as a result of exposure to germs or through vaccination. If your immune system is exposed to the same disease organism over and over, it recognizes the germ as a threat and produces antibodies to fight it.
Sometimes, the immune system can’t tell the difference between your own cells and those of the invading germs. This is called an autoimmune response, and it causes the immune system to attack healthy cells in the body. To avoid an autoimmune response, eat a diet high in antioxidants. Try including oranges, berries and leafy greens in your meals to get vitamin C and folate, and include nuts and seeds to get protein, magnesium and zinc. Get enough sleep and practice stress-reduction strategies such as meditation, journaling or yoga. Long-term stress promotes inflammation, which can disrupt immune cell function and increase your risk for infection.
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