Useful, easy to get tired means you are tired. The reason why the human body feels tired is because all activities of the human body need energy. The main essence of fatigue is the imbalance between energy metabolism ability and energy consumption of human cells. Cetin (cell food) can quickly and effectively supplement various nutrients for human cells, and at the same time, it can produce oxygen in the body and increase the oxygen content in human blood circulation. Cells have enough oxygen, which is conducive to the full oxidation (combustion) of three high-productivity nutrients (sugar, fat and protein) in cell mitochondria, and generates energy for life activities. Cell food is beneficial to strengthening physical fitness and anti-fatigue.