The recommended daily intake of water for an average adult varies but is generally around 3.7 liters (about 13 cups) for men and 2.7 liters (about 9 cups) for women. This intake includes all beverages and food sources of water. Adequate hydration is essential for maintaining body temperature, supporting joint lubrication, and ensuring optimal organ function. Individual requirements may vary based on factors such as activity level, climate, and health status, so it is important for individuals to listen to their bodies and adjust their intake accordingly.