Which of the following factors can contribute to intestinal permeability?

Stress is recognized as a significant factor that can contribute to intestinal permeability, often referred to as "leaky gut." When an individual experiences stress, whether it is acute or chronic, it can lead to a variety of physiological changes in the body. Stress activates the hypothalamic-pituitary-adrenal (HPA) axis, resulting in the release of stress hormones such as cortisol. Elevated levels of these hormones can disrupt the integrity of the intestinal barrier, making it more permeable to toxins, bacteria, and undigested food particles. This compromised barrier can result in inflammatory responses and various gastrointestinal issues.

In contrast, regular exercise typically promotes gut health and can enhance the integrity of the intestinal barrier by improving circulation and reducing systemic inflammation. A high-protein diet does not have a direct correlation with intestinal permeability in most contexts and can actually be beneficial for gut health, depending on the balance and type of proteins consumed. While low hydration may affect overall digestive function, it is not a direct contributor to increased intestinal permeability in the way that stress is.