Co-morbid chronic diseases can be caused by the same immortal pathogens and combinations of pathogens. Treating the root cause of one chronic disease can improve co-morbid diseases caused by the same pathogens. For instance, heart disease, lung disease, Alzheimer’s, and macular degeneration can all be caused by the same pathogen. When Dr. Merchant diagnosed and treated the root causes of chronic diseases, patients would report their unreported symptoms improved and would ask him how he did it when they had not told him about the symptoms. The common causes of co-morbid diseases can be overlooked when each condition is treated by a different specialty, or the history and doctor visit are directed at only one chronic disease.