Hydrogen comes in two flavors. The hydrogen you know which is actually called protium. And deuterium which has all of the same properties as hydrogen except it's twice as heavy. This is due to an added neutron to go with the proton in the nucleus. Because of this, deuterium is also referred to as "Heavy Hydrogen". In nature, deuterium helps things grow. For example, high levels of deuterium is biologically wanted in babies, teenagers, and growing plants and animals. But once you stop growing, having too much deuterium in your cells can lead to premature aging, metabolic problems, and disease. Deuterium is like thick, gluggy oil -- when you put thick oil into an engine, the engine sputters, makes strange noises, and eventually breaks. Evolution has put systems in place to deplete deuterium and protect the "little engines" in our cell's mitochondria called nanomotors from coming in contact with this thick oil. However, the side effects of a modern life - pollution, global warming, processed foods, less healthy lifestyle, etc. - have resulted in many people having way too much deuterium inside their cells. This results in an inability to effectively deplete deuterium and the destruction of our nanomotors. This starts a vicious cycle of deuterium building up and breaking more of our nanomotors. Less nanomotors means less energy and more sickness and disease.