Department of Health

The most vital substance for a healthy mind and body is water.

Age-related changes make older people more prone to dehydration. Renal function and sensitivity to anti-diuretic hormone (ADH) decrease in some older people. Sense of thirst also appears to be reduced, even in healthy older people. Decreased mobility, confusion or dementia and pathological conditions such as hypertension, heart and renal disease make older people highly sensitive to fluid and electrolyte imbalances.

Dehydration makes people tired, cranky and stiff-jointed. It can make it harder to be patient with others. It can bring on headaches, nausea, aches, cramps and other more serious physical ailments. Severe dehydration can cause seizures, coma or death.

Benefits of hydration

  • Boosts physical and mental staying powerHelps keep a pleasant outlook
  • Prevents muscle cramps in legs, hands and feetPrevents achy stiffness in joints
  • Prevents some headaches
  • Flushes out toxins
  • Keeps digestive system working, softening stools and making them easier to pass
  • Helps prevent urinary tract infections by flushing bacteria away

It is important for people to drink before they feel thirsty.

Dehydration: what to look for and what to do

Mild dehydration

Look for: thirst, dry lips, dry mouth, flushed skin, fatigue, irritability, headache, darker urine, decreased urine output.

What to do: Increase fluid intake


Look for: signs of mild dehydration plus a very dry mouth, sunken eyes, skin that does not bounce back quickly when pressed, limited urine output, dark yellow urine, cramps, stiff or painful joints, severe irritability, fatigue, severe headache.

What to do: Call a medical professional

Severe dehydration

Look for: signs of mild and moderate dehydration plus blue lips, blotchy skin, confusion, lethargy, cold hands and feet, rapid breathing, rapid and weak pulse, low blood pressure, dizziness, fainting, high fever, inability to urinate or to produce tears, lack of interest in drinking fluid.

What to do: Call emergency number

Reviewed 19 February 2016


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