Connecting the Dots: Hydration, Micronutrients, and Immunity.

Dehydration, often unnoticed, can occur in adults due to heat-related illnesses, viral infections, and upper respiratory tract infections, leading to deficits in fluids, electrolytes, and energy (FEE), even without diarrhea. This fluid deficit, in turn, impairs immunity at cellular and molecular levels. Physiologically, the immune system rapidly reacts to threats by adjusting its structural permeability, allowing water and small solutes to be passed, facilitated by proteins like aquaporins (AQPs). These AQPs are also essential for immune cell communication and adjustments of the cytoskeleton for functions like chemotaxis and phagocytosis. Apart from hydration, maintaining an optimal intake of essential micronutrients, including vitamins C and E, copper, zinc, and selenium, is also critical for supporting immune function and acting as antioxidants. Transient alterations in immune function caused by acute stressors or nondiarrheal conditions heighten vulnerability to coexisting illnesses, particularly cold and upper respiratory tract infections, while also elevating the likelihood of recurrent health issues. Supplementing fluids with known FEE content according to quality standards and enhanced taste is recommended during acute illness and until complete recovery. Thus, dehydration, caused by various acute conditions, can impair immunity and delay recovery. Prioritizing hydration and nutrition in healthcare and general settings is imperative, even when diarrhea is absent.