Leads to low sodium levels or brain swelling; usual intake per day should be eight to 10 glasses; overhydration can lead to water intoxication

With mercury levels rising, doctors maintain that staying hydrated was essential but overdoing it may not be the best road to take.

Recent research has indicated that overhydration or excess fluid accumulation can lead to dangerously low sodium levels in the blood or cause brain swelling, especially among the elderly, the doctors said.

K. K. Aggarwal, immediate past president, Indian Medical Association (IMA), said, “Overhydration can lead to what is known as water intoxication. In this condition, the amount of salt and other electrolytes in the body become too diluted.”

“A person who drinks the normal amount of water has straw-coloured to transparent yellow urine. Although most people believe that clear urine is the healthiest sign of hydration, but urine with no pigmentation at all may be an indication that one is drinking too much water,” he added.

One should normally intake eight to 10 glasses a day, the doctors said.

“This varies depending on an individual’s height, weight and exercise patterns. Drinking a lot of water or not having an effective mechanism to remove it from the body can cause water levels to build up. This in turn dilutes important substances in the blood. Endurance athletes, such as those who run marathons and triathlons, sometimes drink too much water before and during an event,” he said.

Common symptoms

Some common symptoms of overhydration include nausea, vomiting, headache, and changes in mental state such as confusion or disorientation. If left untreated, it can lead to muscle weakness, spasms, or cramps, seizures, unconsciousness, and coma.

Hyponatremia occurs when concentration of sodium in the blood is abnormally low. Sodium is an electrolyte and helps regulate the amount of water in and around cells. When one drinks too much water, it simultaneously leads to a rise in the body’s water levels and the cells begin to swell. This swelling can cause many health problems from mild to life-threatening.

“Some other conditions that can cause hyponatremia includes certain medications, problems with the heart, kidney, or liver; chronic diarrhoea, and hormonal changes. It is important to trace the cause and take adequate precautions to prevent overhydration, failing which the condition can become critical,” said Dr. Aggarwal.

Jitendra Kumar, director, Nephrology and Kidney Transplant Unit, QRG Health City, said daily intake of water should be spaced.

“Do not drink excessive water immediately after food because it impairs digestion by increasing gut pressure and diluting digestive enzymes. If water is continuously taken in too much quantity, it may lead to kidney stones and chronic kidney diseases.”

He added that sudden dehydration may lead to acute kidney failure and unconsciousness. People who had kidney or cardiac failures are usually unable to tolerate excessive fluid intake. In such conditions, fluid intake should be restricted as per the doctor’s advice.

Gaurav Jain, senior consultant, Internal Medicine, at Dharamshila Narayana Superspeciality Hospital, said, “It is true that drinking too much water can also cause complications. You have to understand your body’s requirement of water. One litre of water per 15 kg of body weight is the actual water requirement of the body.”

“To fulfil water requirement of the body, it is essential to consume 50% plain water and 50% in the form of other water sources like fruits, milk, vegetables, etc., which also complete the electrolyte level in the body. Consuming too much water can dilute existing sodium and potassium from the body, which is known as dilutional hyponatremia. Not only this, but excess water can also lead to complications in a person with a weak heart and kidneys,” he advised.