Water is a great choice for staying hydrated. After all, water is calorie-free, inexpensive and readily available. Still, water isn't your only option. Remember that food also contributes to your daily fluid needs. Many fruits and vegetables, such as watermelon and tomatoes, are 90 percent or more water by weight. Beverages such as milk and juice also are composed mostly of water. In moderation, even beer, wine and caffeinated beverages, such as coffee, tea or soda, can contribute to your daily fluid needs.