Why drinking 6-8 glasses of water can add years to your life

Explaining the study, Dr Dhiraj Bhattad, Consultant, Internal Medicine, Sir H N Reliance Foundation Hospital and Research Centre, says, “Sodium level served as a proxy for water consumption since high levels closely align with hypohydration or water insufficiency, though there are many other controlling factors, including kidneys.”

So how much water should a person be really drinking? “Modern medical science also does not give any definite answer. Few societies recommend six to eight glasses of water or approximately 2 litres/day. But it is not a ‘one size fits all’ recommendation. Our thirst centre usually guides us regarding water intake. Only in older individuals, it may not be that sensitive or they may avoid drinking water to avoid frequent visits to the washroom, especially if they are incontinent. Older adults, who are well hydrated, have been found to have fewer falls, lesser constipation problems and a lower risk of urinary tract infections. People who do more physical work or intense sporting activities, are in a hotter environment or have more protein or salt intake, should consume more water. On the contrary, water intake should be limited in patients with heart and kidney issues. Unnecessary intake of more water may lead to a risk of hyponatremia,” adds Dr Bhattad.

He mentions a population survey that found that about 50 per cent of people do not drink recommended amounts, including children. “Hence, adequate hydration is important for all ages, to help us live healthier and longer. Only hydration alone won’t suffice unless you have healthy nutritious food, exercise and take good care of your illnesses, if any,” he says.

Researchers at the NIH’s Laboratory of Cardiovascular Medicine performed a cohort analysis of data from 1985 to 2021 as part of the “Atherosclerosis Risk in Communities Study (ARIC).” At the time of enrolment, ARIC’s participants ranged from 45 to 66 years old. The study’s 15,752 participants were followed for 25 years. “Our study suggests that long-term habitual hypohydration increases the risk of developing chronic diseases later in life and dying at a younger age,” Dr Dmitrieva said.

Among young adults and middle-aged people, the average amount of water intake varies by age, according to the Centres for Disease Control (CDC). For ages 20-39, the CDC suggests an average of 51 ounces daily. For ages 40-59, 43 ounces of water per day is the average. Some individuals with a higher body mass index (BMI) may need more water. Dr Dmitrieva also suggested that coffee, tea, and electrolyte beverages can count in meeting your hydration goals “but generally, they should not be your main hydration source. Choosing plain water or adding cucumber, lemon, or lime is most advisable as your main source of hydration for optimal heart health.” She added that water-rich foods, in which 90 per cent or more of their content is water, are also good options. Hydrating foods include watermelon, cucumber and strawberries.