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Heuristic daily water estimate

Selected model: 30 mL/kg + 500 mL per hour of activity + 500 mL in heat. An assumed 75% comes from drinks; a glass is 250 mL. No age-related reduction is applied.

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Calculation

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The result updates as you change the fields. Your data never leaves the browser.

This calculation is for reference only and is not medical advice, a diagnosis or a prescription. If you have a medical condition, are pregnant, take medication or have any doubts, discuss the result with a physician or a qualified nutrition professional.

Result

Total water
2500 ml/day

Selected model: 30 mL/kg + 500 mL per hour of activity + 500 mL in heat. An assumed 75% comes from drinks; a glass is 250 mL. No age-related reduction is applied.

Of that, from drinks
1880 ml/day

Selected model: 30 mL/kg + 500 mL per hour of activity + 500 mL in heat. An assumed 75% comes from drinks; a glass is 250 mL. No age-related reduction is applied.

Equivalent
8 glasses
Volume in ounces
85 fl oz/day

Equivalent in US fluid ounces (fl oz)

Baseline requirement
2250 ml/day
Activity adjustment
250 ml/day
Climate adjustment
0 ml/day

These are model assumptions, not EFSA requirements. EFSA total water from drinks and food is 2.0 L for women and 2.5 L for men, the same for adults and older adults under moderate conditions. Actual sweat losses and disease-related limits need separate assessment.

Distribute these calories into protein, fat and carbs

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How it is calculated

Selected model: 30 mL/kg + 500 mL per hour of activity + 500 mL in heat. An assumed 75% comes from drinks; a glass is 250 mL. No age-related reduction is applied.

Formula

Selected model: 30 mL/kg + 500 mL per hour of activity + 500 mL in heat. An assumed 75% comes from drinks; a glass is 250 mL. No age-related reduction is applied.

Limits of the method

These are model assumptions, not EFSA requirements. EFSA total water from drinks and food is 2.0 L for women and 2.5 L for men, the same for adults and older adults under moderate conditions. Actual sweat losses and disease-related limits need separate assessment.

Sources of the method

  • EFSA Panel on Dietetic Products. Scientific Opinion on Dietary Reference Values for water, 2010
  • American College of Sports Medicine et al. American College of Sports Medicine position stand. Exercise and fluid replacement. Med Sci Sports Exerc, 2007

How to use the calculation

1

Enter the starting values

Selected model: 30 mL/kg + 500 mL per hour of activity + 500 mL in heat. An assumed 75% comes from drinks; a glass is 250 mL. No age-related reduction is applied.

2

Adjust the parameters

Selected model: 30 mL/kg + 500 mL per hour of activity + 500 mL in heat. An assumed 75% comes from drinks; a glass is 250 mL. No age-related reduction is applied.

3

Read the result

These are model assumptions, not EFSA requirements. EFSA total water from drinks and food is 2.0 L for women and 2.5 L for men, the same for adults and older adults under moderate conditions. Actual sweat losses and disease-related limits need separate assessment.

Frequently asked questions

What does the calculation show?

Selected model: 30 mL/kg + 500 mL per hour of activity + 500 mL in heat. An assumed 75% comes from drinks; a glass is 250 mL. No age-related reduction is applied.

What limitations apply?

These are model assumptions, not EFSA requirements. EFSA total water from drinks and food is 2.0 L for women and 2.5 L for men, the same for adults and older adults under moderate conditions. Actual sweat losses and disease-related limits need separate assessment.

Related calculators

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  • Dietary fibre reference intakes
  • Estimated sweat loss during exercise
For professionals

Calculation assumptions

These are model assumptions, not EFSA requirements. EFSA total water from drinks and food is 2.0 L for women and 2.5 L for men, the same for adults and older adults under moderate conditions. Actual sweat losses and disease-related limits need separate assessment.

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