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Medicine & Health

What is The immune system?

The immune system is your body's defense network against germs. It spots invaders like bacteria and viruses, attacks them, and remembers them — so the next time the same germ shows up, it's defeated faster. Vaccines train it safely.

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Key things to understand

  • 1Your body's defense network against germs.
  • 2It detects, attacks, and remembers invaders.
  • 3White blood cells do much of the fighting.
  • 4Memory cells make future responses faster.

Frequently asked questions

How does the immune system protect us?
It recognizes germs as foreign, destroys them with white blood cells and antibodies, and remembers them for a faster response next time.
What weakens the immune system?
Poor sleep, chronic stress, poor nutrition, and some illnesses can all reduce how well it works.
How do vaccines help the immune system?
They show it a harmless piece of a germ so it builds memory and protection without you getting sick.

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