Which of the following could potentially worsen nausea during treatment?

The selection of stress as a potential factor that could worsen nausea during treatment is grounded in the established link between psychological states and physical symptoms. Stress can provoke the body's fight-or-flight response, which may affect various physiological systems, including the gastrointestinal tract. Under stress, the release of hormones such as cortisol and adrenaline can lead to increased gastric motility or delayed gastric emptying, exacerbating feelings of nausea. Additionally, stress might heighten sensitivity to nausea triggers and lower the effectiveness of antiemetic agents, leading to a worsening of symptoms.

In contrast, regular exercise, a healthy diet, and adequate hydration are generally supportive of overall health and can help mitigate nausea. Exercise can promote the release of endorphins, which can improve mood and potentially reduce feelings of nausea. A healthy diet can ensure nutritional balance and may provide the body with the necessary nutrients to cope better with treatment side effects. Hydration is critical, as it helps maintain electrolyte balance and can reduce nausea associated with dehydration. Thus, stress stands out as a factor that could significantly worsen nausea during treatment.