How is obesity defined?

Obesity is defined as a condition characterized by high fat content due to energy imbalance. This means that it occurs when the number of calories consumed exceeds the number of calories expended over a significant period. As a result, excess energy is stored in the body as fat. This definition emphasizes the critical role that energy balance plays in determining body fat levels and highlights the importance of understanding how dietary habits and physical activity levels contribute to one's overall health.

In contrast, the other definitions relate to fitness or health status rather than strictly to obesity itself. A state of physical fitness involves various components such as cardiovascular endurance, flexibility, and muscle strength, which do not directly correlate with obesity. Regular exercise refers to the activity aimed at improving fitness and health and is not synonymous with obesity. Similarly, a description of excellent health encompasses a wide range of factors beyond just fat content, including physical fitness, mental wellbeing, and absence of illness, none of which define obesity itself.