Drinking too much water?
“I make it a point to drink a LOT of water daily.”
“If my urine colour is not as clear as water, I am drinking too less water.”
“I get up four times at night to urinate, but that’s because I have to drink a litre of water before I go to bed.”
These are some of the typical statements that I hear in the hospital, every day. People are obsessed with drinking a LOT of water. Sometimes, I have mothers who bring their 20-plus-year-old children with this complaint, “she doesn’t drink water at all!” One of them even offered, “If you don’t spend enough time in the bathroom, you’ll spend time in the emergency room!”
Here’s a clarification before you think I am asking everyone to drink less water. I’m not.
How much water should we drink per day?
It is a prevalent notion that the more water you drink, the better it is for you. This statement is not applicable to everyone.
How much water you should drink depends on your age, sex, activity level, and any medical conditions that you may have. Most of us need modest water intake. Some may need a higher intake.
However, there are also a diverse set of people, who should drink less water to remain healthy.
1. Moderate water intake
Most young and healthy individuals need a modest water intake. How much is modest? That’s drinking water when we are thirsty.
Quench your thirst; there is no need to drink gallons of water, unless, of course, you enjoy your time in the bathroom. As long as you are ‘young’ and ‘healthy’, it is okay to drink water in quantities that you find ‘more than enough’ too.
Generally, subject to the prevailing weather and our activity level, water requirement is about 2.5 litres per day. Our water intake includes all the water in various foods that we consume through the day – including the water content in the food and beverages that we consume. Please remember that fresh fruits and vegetables have high water content.
The normal colour of urine is not “clear like water”, but pale yellow. Drink water when you are thirsty, instead of trying to control the colour of your urine.
2. High water intake
People who tend to form kidney stones need to drink a slightly higher volume of water than the rest of us. Research has shown that most people need to pass about 2.5 litres of urine per day to avoid kidney stone formation. This will amount to about 3.0 – 3.5 litres of water intake, depending on the weather and physical activity level.
Those with constipation need to consume water enough to avoid dehydration. High dietary fibre intake is more important than higher water intake.
3. Water restriction
In my medical practice over the last two decades, I have seen scores of patients who have come with symptoms produced solely due to excessive water intake (because their neighbour or friend told them). Many of them develop significant symptoms and have required hospitalisation after drinking too much water. Some have even needed treatment in intensive care units.
Too much of anything is too bad. Including water. There is a popular proverb in India – “Even elixir when in excess, is a poison”.
What are the important ill-effects of excessive water intake?
- Overload on the heart
- Overload on kidneys
- Dilution of salt in the blood, causing hyponatremia (low sodium level in blood)
- Swelling of brain cells (due to hyponatremia)
Who needs to restrict their water intake?
- People with heart diseases, kidney diseases, and other illnesses that may affect water balance should consult their doctor regarding their maximum safe water (and salt) intake per day. Consuming excess water often produces swelling of feet initially, but eventually, progress to a life-threatening complication called pulmonary oedema (swelling of the lungs – best described as flooding in the lungs). Pulmonary oedema produces severe breathlessness and may require emergency hospitalisation.
- People with hyponatremia (and those who have just recovered from hyponatremia) need to mind the amount of water they consume. Drinking too much water in this situation can cause dilution of blood and consequently, low sodium levels. Hyponatremia can result in confusion, seizures and coma due to brain cell swelling. Hyponatremia is a life-threatening condition too.
- People who are taking certain medications like anti-inflammatory agents (pain relievers), some antihypertensives (to control blood pressure), or steroids, also need to consult their doctor regarding the amount water (and salt) they can consume per day. You may need to avoid excessive water and salt intake.
Some people tend to drink more water compulsively – we call this Psychogenic polydipsia. One of the features of psychogenic polydipsia is hyponatremia, described above.
Most people have heard of alcohol intoxication. But water intoxication? It’s not like getting high on water! It is the flooding our body with water, causing hyponatremia and overload on our heart and kidneys.
Water is good for you, as long as you do not overdrink it. Remember – too much is too bad. If you do what your body demands you to, as indicated by thirst, you’ll probably be safe.
Just as you need to eat right, you need to drink right too.
You certainly do not want your body in this state:
Shashikiran teaches Internal Medicine at MMMC, Manipal Academy of Higher Education, and has clinical responsibilities at the Department of Medicine, Dr TMA Pai Hospital, Udupi, Karnataka, India.