Unfortunately, the North American diet is far too high in meat protein, animal fat, refined sugar, starches, caffeine, and a host of additives, which cells can't deal with. Over time, cells cease to be able to function efficiently, and so does the body. Even if we return to a healthy diet, cells will probably need a degree of restoration from past maltreatment. In order to ensure proper functioning of all cells, body fluids need to be kept moving. This can be accomplished only by exercise.
Exercise is absolutely essential for building and maintaining healthy cells.
Exercise puts oxygen into the blood, keeps the lymph moving and helps maintain the general health of the entire body. It strengthens and nourishes all the various organs and systems of the body. But if we don't exercise, cells produce more energy than needed, and store the excess as fat. Over time, we can increase body weight to the point where we don't want to exercise, and even start to damage our cell structures. The environment we live in is important to our health.