Your immune system is your intricate defense system comprising many biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, known as pathogens, from viruses to parasitic worms, and distinguish them from the organism’s own healthy tissue. In your body, there is what is known as the blood–brain barrier, blood–cerebrospinal fluid barrier, and similar fluid–brain barriers separate the peripheral immune system from the neuroimmune system, which protects the brain. To prevent disease and damage it is important for you to provide optimal support for this system. This is achieved with eating whole fresh foods, obtaining and maintaining healthy lifestyle habits.