It seems like your sentence got cut off. However, I can clarify that the body requires oxygen to efficiently convert the food we eat into energy. This process primarily occurs in the cells through a metabolic process called cellular respiration.
In cellular respiration, glucose (derived from the food) is broken down in the presence of oxygen to produce ATP (adenosine triphosphate), which is the energy currency of the cell. The overall equation for this process can be summarized as:
\[ \text{Glucose} + \text{Oxygen} \rightarrow \text{Carbon Dioxide} + \text{Water} + \text{Energy (ATP)} \]
Without sufficient oxygen, the body cannot efficiently produce ATP, leading to fatigue and other health issues. In situations where oxygen is limited, the body may resort to anaerobic respiration, which is less efficient and can lead to the production of lactic acid. If you have more specific questions or need further information, feel free to ask!