Toratani Co., Ltd. in Kahoku City, Ishikawa Prefecture, is continuing its Night Oxygen Flow Project, which aims to clarify the realities of breathing infrastructure during sleep, and has released a new analysis on the latest theme. The project organizes, from a physiological perspective, how shallow breathing affects the autonomic nervous system, blood flow, and metabolism, and will apply these findings to future awareness activities and product development. Breathing is not merely the movement of air in and out. It is a hierarchical engine that drives the body. When breathing becomes shallow, oxygen, the autonomic nervous system, and the internal bodily environment quietly fall out of balance, gradually weakening sleep, metabolism, immunity, and many other functions. Breathing is the most upstream engine of life. The body operates along a single causal line: breathing, then oxygen and the autonomic nervous system, then the internal environment, and finally whole-body function. When breathing is deep, this entire line runs smoothly. When breathing is shallow, the functions of the whole body quietly decline. When breathing becomes shallow, oxygen deficiency occurs first, followed by disruption of the autonomic nervous system. As a result, the internal bodily environment, including metabolism, immunity, and body temperature, becomes unstable. This is the very structure in which a weakened upstream engine causes downstream functions to decline in sequence. The depth of breathing is determined by the physics of sleep. Three factors occur during sleep: changes in airway angle, sinking of the rib cage, and restriction of the diaphragm. These are the physics of breathing under a 90-degree shift in gravity. When a person lies down, the direction of gravity changes, creating a structure in which anyone can more easily experience shallow breathing. Viewed as a hierarchy, improving the quality of breathing upstream in the body is connected to preventing illness and maintaining