As a person ages, he feels less thirsty, so a special effort should be made to provide enough fluids. A person's fluid balance can be affected by medication, emotional stress, exercise, nourishment, general health, and the weather. Dehydration, especially in the elderly, can increase confusion and muscle weakness and cause nausea. Nausea, in turn, will prevent the person from wanting to eat, thereby causing more dehydration.

Preventive measures include:

• encouraging 6-8 cups of liquid every day (or an amount determined by the doctor)
• serving beverages at room temperature
• providing foods high in liquid (for example, watermelon)
• avoiding caffeine, which causes frequent urination and dehydration