Experts Decode: Do You Really Need 8 Glasses Of Water A Day?

The ideal intake of water a day depends on several factors.

Published On Apr 11, 2022 | Updated On Mar 05, 2024


While the human body can go without food for three weeks, research suggests it cannot go more than three to four days without water. There's no doubt that the human body depends on a regular intake of water for its survival. After all, 60 per cent of an average adult human body is made up of water, states a report by the US National Institute of Health.

This elixir of life plays multiple roles in the human body – from regulating its internal temperature and transporting nutrients to lubricating joints. All of us are aware of the 'eight glasses of water a day' adage but how accurate is this recommendation?

Eight glasses of water a day, which is about two litres, is said to be the ideal amount to keep the human body hydrated but does this hold true for everyone? Munmun Ganeriwal, a nutritionist and fitness consultant says, "Drinking eight glasses of water a day is a reasonable goal to remember but hydration needs differ from person to person."

The founder of Yuktahaar, a Mumbai-based nutrition and exercise consultancy, explains, "For some, drinking lesser than eight glasses could work but there may be some who may require more than that.”

© Canva

Apart from being different for every individual, the adequate amount of water intake also depends on factors such as the season, where one lives, one's level of physical activity and overall health status. For instance, those who follow a regular workout routine may require more water to make up for the fluid lost during exercise.

The body also tends to lose fluids and electrolytes rapidly when one is sick, particularly when experiencing fever, vomiting or diarrhoea. Women who are pregnant or lactating also need to up their water intake to stay hydrated.

The best way to know whether your body is hydrated enough is to do a quick urine check. "The colour of your urine is a good way to tell," suggests Ganeriwal. "If it is colourless, that's a good sign but if it is dark then it's time to drink more water," she explains.

Many people think that drinking excess water can be harmful to the body. But, according to Ganeriwal, it is rare that someone can have so much water that it becomes harmful. "Excess water can cause hyponatremia or low levels of sodium, but it’s not very common,” she says. 


Now that we know it's not so much the amount of water but ensuring that our body is well hydrated at all times, here's a look at the benefits of drinking water regularly through the day:

Great for skincare: Water keeps the insides of the body hydrated and one of the benefits of this is great skin. “Drinking enough water and maintaining the hydration status of the body gives elasticity to the skin, keeping it supple," explains Ganeriwal, and adds, "The moisture that the skin receives through water prevents early signs of ageing such as wrinkles and fine lines.”

Better digestion: The most underrated but important function of water is that it aids digestion. Sipping on water at regular intervals throughout the day prevents digestive discomfort such as constipation, indigestion and irritable bowel syndrome (IBS). The regular intake of water makes sure to cleanse your stomach and digestive system. 

© Canva

Weight loss: Drinking sufficient water helps boost metabolism and accelerates the process of fat burning in the body. Ganeriwal explains, “A study published in the Journal of Clinical Endocrinology and Metabolism found that those who drink about 500 ml of water witness a 30 per cent increase in their metabolic rate. At the same time, mild dehydration can cause the metabolic rate to slow down by as much as 3 per cent." 

Detox: When the body is dehydrated, the kidneys are unable to perform optimally and cause the buildup of toxins in the body. Drinking water helps to cleanse or detoxify the body and reduces the risk of kidney stones.

Heart health: Drinking water is good for the heart too. Ganeriwal explains, "Water helps maintain blood viscosity, plasma and fibrinogen distribution. A heart that is well-hydrated pumps blood more easily thus drinking water also improves blood circulation.” For a healthy heart, it is also important to be aware of where the trans fats hide in your food.

© Canva

Water, although essential, is not the only way you can keep your body hydrated. There are other sources that replenish the body's fluids as well. Several fruits and vegetables, rich in water content, can help to keep the body hydrated. “Cucumber, watermelon, strawberry, banana, coconut water, buttermilk, tomato, pineapple and orange are some foods with high water content," says Ganeriwal. Turning vegetables into juice is a great way to stay hydrated.

Photo: Shutterstock and Canva