Which of the following can increase fluid and nutrient loss in the body?

The presence of illness is a significant factor that can increase fluid and nutrient loss in the body. When an individual is ill, especially with conditions such as fever, diarrhea, or vomiting, there is often an increased demand for fluids and nutrients. The body requires more resources to fight the infection, repair tissues, and maintain overall metabolic functions. Illness can also impair the body's ability to absorb nutrients efficiently, leading to further deficiencies.

For instance, infections can cause inflammation that alters the permeability of the gastrointestinal tract, making it harder for the body to take up nutrients. Additionally, illnesses can lead to symptoms like sweating, which can result in fluid loss. Thus, the physiological processes associated with various illnesses create a situation where fluid and nutrient loss is markedly increased, necessitating careful management and replenishment.