What is a common factor affecting the susceptibility to skin infections?

A weakened immune system is a significant factor affecting the susceptibility to skin infections because the immune system plays a crucial role in defending the body against pathogens, including bacteria, viruses, and fungi that can cause skin infections. When the immune system is compromised—due to conditions such as chronic illnesses, medications that suppress immune function, or certain genetic disorders—the body's ability to fight off infections diminishes, making skin infections more likely to occur and potentially more severe.

Age, while sometimes contributing to the overall health status and immune function, does not have as direct an impact on susceptibility to skin infections as the state of the immune system itself. Levels of physical activity can influence general health and, subsequently, immune response, but they are not as directly linked to susceptibility. Similarly, dietary habits can affect overall health and immune function, but the primary factor in this context is the strength or weakness of the immune system. Thus, having a weakened immune system is the key reason why individuals are at higher risk for skin infections.