People get sick because they have been exposed to something (allergen, virus, bacteria, fungus, chemical, heavy metal, radiation, mineral etc.) at a time or in a fashion that your body was unable fight it off. Our bodies are extremely resilient to most exposures, unless we are nutritionally or immuno-compromised. Preventive Medicine addresses health in two ways: removing and eliminating exposure of harmful substances and assuring that our bodies maintain a state of optimum health with proper nutrition, sleep, exercise and limitation of stress.