Water and Your Body: How Much Should You Really Drink?

You have probably heard that you must drink eight glasses of water every day. The truth is more relaxed. Your body does need water for almost everything it does, but the right amount depends on you.

What water does for you

Water makes up a large part of your body. It carries nutrients in your blood, helps control your body temperature through sweat, cushions your joints, and helps your kidneys clear waste. Even mild dehydration can cause headaches, tiredness, and trouble concentrating.

So how much is enough?

The US National Academies of Sciences suggested a total water intake of about 3.7 litres per day for men and 2.7 litres for women. Two important details are often missed:

• This number includes water from all drinks and from food. Fruits, vegetables, soup, and curd all contain water, and food gives roughly 20 percent of the total.
• It is a general average, not a personal target. You need more in hot weather, during exercise, when you are ill with fever or diarrhoea, and when you are pregnant or breastfeeding.

Easy signs you are drinking enough

1. Check your urine colour

   Pale yellow, like light lemonade, is a good sign. Dark yellow or amber usually means you need more fluids.

2. Notice your mouth and lips

   A dry mouth, sticky saliva, or cracked lips are early signals.

3. Watch for headaches and tiredness

   If they appear on hot or busy days, try a glass of water before reaching for a painkiller.

4. Look at the timing

   You should pass urine every few hours during the day. Going once or twice a whole day is a warning sign.

Tips that make drinking water easy

• Keep a bottle where you can see it, such as on your desk.
• Drink a glass after you wake up and one with each meal.
• Add lemon, mint, or cucumber if plain water feels boring.
• Eat water-rich foods like watermelon, oranges, and cucumber.

What most people miss

• Tea and coffee count. The old idea that they dry you out is mostly a myth for people who drink them regularly. They contribute to your daily water.
• More is not always better. Drinking huge amounts of water in a short time can lower the salt level in your blood, a rare but serious condition called hyponatraemia. This is mostly a risk during very long endurance events.
• Older adults feel thirst less. Their sense of thirst weakens with age, so they should drink regularly through the day.

Sources

• Mayo Clinic: Water, how much should you drink every day?
• NHS: Water, drinks and hydration