The immune system is responsible for defense against infectious agents, and is composed of leukocytes, macrophages, and lymphocytes. When immunity levels are low, the body is more likely to become infected with viruses, bacteria, and others. People who are easily infected can have low immunity for various reasons, such as family history diseases, poor diet, or absorption difficulties in some body function. Maintaining the intake of substances that strengthen immunity is to prevent diseases and prepare the body for any possible infection. To do this, it is important to turn your attention to what is ingested, exercise habits, and supplementation.