Your immune system is like a sentry on guard 24 hours a day. Or a militia ready to stop any intruder that poses a threat to your health. But who guards the guards? Who protects the protection? You do. That’s where a smart diet and healthy lifestyle come in. By knowing
how your immune
system works and what foods strengthen it, you can help your immune system run at maximum efficiency. How it works. Trouble can strike your body at any time. Bacteria, viruses, fungi, and parasites attack from the outside, while cancer cells attack from within. Any of these foreign substances, called antigens, stimulate the immune response. Your body counters with its army of white blood cells, including phagocytes, T cells, and B cells. They recognize the intruder, mobilize forces, and attack. For example, T cells recognize foreign invaders and kill them by breaking them apart. B cells respond to infection by releasing antibodies, proteins that surround and immobilize the antigens. T cells and B cells also have great memories. Once they’re exposed to an antigen, they remember it in case it comes back. That’s how vaccines work.

Of course, your immune system doesn’t always work perfectly. It can overreact to a harmless substance, resulting in an allergic reaction, like hayfever or hives. Sometimes, your immune system can even turn against your own body. That’s what happens in autoimmune diseases like rheumatoid arthritis, lupus, and type 1 diabetes. When you get sick, it’s often because the antigen was able to do some damage before your immune system destroyed it. Or because your immune system wasn’t strong enough to fight it off.