Diversified heterogeneous things are collided and merged with each other to achieve a meta-whole state and process with the function of 'living' under certain laws or rules, which is called 'harmony'. The state of health of the human body is the state of 'harmony'. Keeping the human body's normal state of harmony is preserving health, so the concept of preserving health in traditional Chinese medicine is called 'keeping harmony', namely keeping the 'harmony' of health. How to keep it? We should start from people's daily life, including diet, living, exerc...