Which nutrient is essential for human survival?

Water is essential for human survival because it plays a critical role in numerous bodily functions. All living organisms, including humans, require water to maintain homeostasis, regulate body temperature, and facilitate cellular processes. It is involved in digestion, circulation, and excretion, as well as serving as a solvent for nutrients and a medium for biochemical reactions. Without adequate hydration, the human body cannot function properly, leading to severe health consequences and even death in extreme cases.

While carbohydrates, proteins, and fats are important for providing energy and supporting bodily functions, humans can survive for a time without food, whereas survival without water is only possible for a matter of days. This highlights the fundamental necessity of water as a nutrient critical for life.