Dehydration is one of the most frequent causes of hospitalization among people over the age of 65.

An article in Nurse Practitioner concluded that "Dehydration is the most common fluid and electrolyte disturbance among the elderly population today."

Water is important to all bodily processes say medical experts. Water carries nutrients, hormones, and disease fighting cells and antibodies to and from body organs through the bloodstream. Water carries carbon dioxide and waste products to the lungs, intestinal tract and kidneys to be excreted.

Hypertension, circulation disorders, kidney stones, arthritis, indigestion and constipation are all common disorders found in elderly people that can be directly, or indirectly, caused in inadequate water intake. Over the age of 65 thirst diminishes and a person is not likely to drink without consciously thinking about it.

A lack of water aids kidney stone development since there isn't adequate water for kidneys to flush out stone forming minerals.

A lack of water causes sodium levels in the body to rise. When not enough water is ingested, the body holds water. This causes fluid buildup and sodium retention. Salt draws water out of the tissues, increasing dehydration. This can result in confusion, excitability, and a host of other problems to which older people are prone to, especially increased blood pressure.

Water is important for digestion and absorption of food. Digestive symptoms such as nausea can be indicative of the need for more water. Constipation, a frequent complaint of elderly Americans is commonly caused by inadequate water intake, says a California nutrition expert.

Joint and muscle stiffness occur as a result of not enough water for lubrication.

Without adequate water, there is stress on the cardiovascular system. Blood becomes thicker so the heart works harder and circulation is slowed. Many elderly people already have a sluggish circulation.

When circulation is sluggish the brain doesn't receive enough oxygen resulting in headaches, dizziness, fatigue, and a loss of mental alertness. A reduction of only 4 to 5 percent in body water will result in a 20 to 30 percent work performance.

Postmenopausal women taking estrogen supplements need to be aware that estrogen acts as a salt retainer. Water is needed to remove the excess salt from the body.

Some common signs of an inadequate water intake are constipation, dark yellow urine, and dry, sticky mouth caused by decreased salivary gland function says a Harvard physiologist. Everyone needs a minimum of eight 8-ounce glasses of water spaced evenly throughout the day.