How much water should you really drink every day?

Daily water intake recommendations have stayed largely unchanged for two decades. Health experts, including those at Barmer, advise adults to drink at least 1.5 to 2 litres of water each day. Yet the exact amount needed can shift depending on individual circumstances.

The long-standing '8-by-8 rule'—suggesting eight glasses of water a day—lacks scientific backing. Instead, official guidelines differ slightly: men should aim for around 3.7 litres (15.5 cups) daily, while women need about 2.7 litres (11.5 cups). These totals include fluids from all sources—water, drinks, fruits, vegetables, and even food.

Certain groups require extra hydration. Those with physically demanding jobs, athletes, people in hot climates, and pregnant or breastfeeding women often need more. Dark urine or signs like dry mouth, cracked lips, and muscle cramps can also signal a need for increased fluid intake.

Simple strategies can help maintain hydration. Drinking when thirsty, sipping water before and between meals, and keeping a water bottle nearby make it easier to meet daily needs.

While general advice remains steady at 1.5 to 2 litres of water per day, individual requirements vary. Factors like activity level, climate, and health all play a role in determining how much fluid a person should consume. Recognising dehydration signs and adjusting habits accordingly can help maintain proper hydration.