The immune system is the body’s natural defense network. It is comprised of many organs, cells, and proteins that work together to protect against outside viruses, bacteria, and other unwanted invaders. When functioning correctly, the immune system identifies which cells are yours and which are foreign. It then organizes to kill any invaders that could cause the body harm. Your immune system does this complex work naturally, but, like anything, it requires a healthy environment in order to thrive. Maintaining a healthy lifestyle can help bolster your immune system.