Water is critical for brain health.

Dehydration is the most common fluid and electrolyte disorder in the elderly adult population. Dehydration occurs when the body’s fluid output is higher than its intake. Water must be replaced daily because the body cannot store it. The human body's water ranges from 50-75%. The average adult human body is made up of 50 – 65% water. People feel thirsty when they have already lost around 2 – 3% of their body’s water. Mental performance and physical coordination start to become impaired before thirst kicks in, typically between 1% and 2%, according to the literature.

Lack of water intake - or dehydration is serious. Consequences of dehydration can include muscle spasm, kidney dysfunction, adverse and dangerous reactions to medications, infections, seizures, hospitalisation, coma and even death. The death rate is 7 times higher for dehydrated patients, and hospitalisation costs for dehydrated patients are more than $1 billion per year in the United States alone. Women tend to be more prone to dehydration than men. Vomiting and diarrhea can cause dehydration as well as some medications such as diuretics, laxatives and sedatives. Caffeine and alcohol consumption can also contribute to dehydration.

1. Weight Loss – Acute weight loss may be the first indicator of dehydration. Each litre of fluid is equivalent to 1 pound or 2.2 kg. The fluid loss should be considered first with any acute weight loss. 

• Mild Dehydration = 5% body weight in one week 
• Moderate Dehydration = 5 – 10% body weight in one week
• Severe Dehydration = 10% body weight in one week

2. Increase in pulse – When body water content decreases, the heart has to work harder to circulate a smaller blood volume. Increased heart rate, or tachycardia, is an indication of dehydration.

3. Dizziness, Decrease in Blood Pressure – A 10% decrease in blood pressure may indicate decreased blood volume, thus dehydration. This can manifest itself in dizziness, unsteady gait, and falls.

4. Changes in Physical Appearance – When a person is dehydrated, the skin will stay in a “tented” position when pinched, for some time. The best places to test for this is the skin of the forehead and chest. A dry tongue that may be cracked or fissured is an indication of dehydration. Mucous membranes will appear dull, and the saliva pool under the tongue will be depleted.

5. Fever – Dehydration can cause an increase in body temperature. The body compensates by raising body temperature to “cool” the body down.

6. Concentrated Urine or Decreased Urine Output – Urine output less than 500 cc’s per day is a sign of dehydration.

7. Constipation and Fecal Impaction – When inadequate fluids are consumed, constipation and fecal impaction may result. Fluids help to push the stool through the GI tract. Constipated people should drink extra fluids.

8. Loss of Appetite – Nausea and anorexia may result from inadequate fluid intake secondary to accumulation of waste products in the body.

9. Sunken Eyeballs – Decreased fluid volume causes eyeballs to appear more buried in the skull than usual.

10.Increased Confusion – Dehydration affects the brain and nerve cells causing generalized weakness, trembling, lethargy and confusion. In severe cases, delirium, hallucinations and manic behaviour may result.

Preventing dehydration from happening in the first place is the best solution to avoiding the dangerous complications from dehydration. Fluid replacement is a distinct treatment for dehydration. Contact your doctor or physician if you suspect dehydration in yourself or in your loved one.