How much water should I drink?
A common guideline is about 35 ml per kg of body weight — roughly 2–2.5 litres for most adults — plus about 350 ml for every 30 minutes of exercise and more in hot weather. That's total fluid: tea, coffee, milk, buttermilk, dal and fruit all count.
Signs you need more
- Dark yellow urine (pale straw is ideal)
- Headache, tiredness or dizziness in the afternoon
- Dry mouth or lips
This is a general guideline, not medical advice. Pregnant and breastfeeding women need more; people with kidney, heart or liver conditions may need to limit fluids — follow your doctor's advice.