--- title: "How much water should you drink each day? | Joy Health" description: "The 2.7- and 3.7-liter adult reference values count plain water, other beverages, and food. Learn what total water means and why needs vary." canonical_url: https://joyhealth.cc/nutrition/hydration published: 2026-08-28 publisher: Joy Health --- Nutrition guide # How much water should you drink each day? The adult reference values are 3.7 liters of total water per day for men and 2.7 liters for women, and total water counts other beverages and food, not just plain water.[1] This guide explains what those numbers count and why they are not precise requirements for every person or day. Prepared by **Joy Health** Published August 28, 2026 ## How much water should you drink? First define total water {#meaning-title} The National Academies uses *total water* to include drinking water, water in other beverages, and moisture in foods.[1] A bottle count includes only one part of that total unless it deliberately accounts for the other sources. The adult numbers are Adequate Intakes, or AIs. They were set from observed median U.S. intakes because the evidence did not support an Estimated Average Requirement and RDA. The report also says a wide range of intakes can be compatible with normal hydration.[1] > **Ask what the number counts.** Total water, beverage water, and plain drinking water are not interchangeable terms. ## How much water per day do the reference values say? {#evidence-title} The water DRI is a population reference for apparently healthy U.S. and Canadian people. Its values describe total water and are best read alongside how they were derived and what they leave out. - **Total-water AI** — The adult AI is 3.7 liters per day for men and 2.7 liters per day for women. These totals include beverages and food and were based on median intakes, not a measured requirement for each individual.[1] - **Beverage estimate** — Among adults ages 19 to 30 in the source data, beverages supplied about 3.0 liters for men and 2.2 liters for women, roughly 81 percent of total water. These are components of the total-water reference, not extra amounts to add.[1] - **Food contribution** — Food moisture supplied about 19 percent of total water in the report's source data. The proportion varies with what a person eats, so 19 percent is context, not a rule for every meal or day.[1] - **Variation** — The National Academies notes day-to-day variation with activity and climate. CDC says recommendations also vary with age, sex, pregnancy, and breastfeeding status.[1][2] ## How to use the daily water reference values {#use-title} 1. **Identify the reference type.** Read 3.7 and 2.7 liters as total-water AIs for adult population groups, not exact requirements or plain-water prescriptions.[1] 2. **Count all stated sources.** Plain water, other beverages, and moisture in food contribute to total water. Do not add the beverage estimate on top of the total-water AI.[1] 3. **Notice the context.** Ordinary conditions, activity, climate, age, sex, and life stage affect how useful a population reference is for a particular situation.[1][2] 4. **Stop where the guide stops.** Heat, prolonged exercise, vomiting or diarrhea, pregnancy or lactation, older age, and fluid-restricted conditions require context this guide does not compress into a formula. A reference, not a jug size A 2.7-liter total-water AI does not mean 2.7 liters of plain water must be consumed in addition to coffee, tea, milk, soup, fruit, or other foods and beverages. All water-containing sources belong to the total. How much comes from each source varies.[1] Comparing plain water with a sports drink or powder? Continue with the guide to [electrolytes versus water](https://joyhealth.cc/nutrition/electrolyte-drinks), which separates hydration, exercise losses, fuel, and extra active ingredients. ## When the daily water numbers do not apply {#limits-title} - The AIs come from older, self-reported intake data and are not measured individual requirements. - The male and female categories are the source report's categories and do not capture every body size, physiology, or circumstance. - The guide does not diagnose dehydration from urine color, thirst, headache, or any single sign. - It does not provide exercise, heat, illness, pregnancy, lactation, or fluid-restriction instructions. Seek qualified care for persistent symptoms, illness, medication-related questions, or conditions that alter fluid or electrolyte needs. Use urgent help for emergencies. ## Sources we read {#sources-title} Both sources were read on August 28, 2026. The National Academies supplies the reference values and derivation; CDC supplies current variability context. Neither provides an individualized assessment. 1. [Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate, Chapter 4: Water](https://www.nationalacademies.org/read/10925/chapter/6) Institute of Medicine, 2005. Used for total-water definitions, AIs, source proportions, variability, and limitations. The values were based on older self-reported median intakes, and the report states that industry contributors helped fund the broader DRI project while conclusions remained those of the authoring panel. 2. [About Water and Healthier Drinks](https://www.cdc.gov/healthy-weight-growth/water-healthy-drinks/index.html) Centers for Disease Control and Prevention. Used only for current factors that vary daily recommendations. Limitation: general consumer guidance, not a clinical formula. Keep reading ## Related guides {#related-guides-title} - Electrolyte drinks **[Electrolytes vs. water: when do you need them?](https://joyhealth.cc/nutrition/electrolyte-drinks)** Carry the hydration and supplement-reading skills into powders, sports drinks, and mixed-purpose active-nutrition products. - Building balanced meals **[How to build a balanced meal without rigid rules](https://joyhealth.cc/nutrition/building-balanced-meals)** A flexible way to notice what a meal already contains and decide whether one practical addition would be useful. - Reading food labels **[How to read a Nutrition Facts label](https://joyhealth.cc/nutrition/reading-food-labels)** A repeatable way to interpret the serving basis, percent Daily Value, ingredients, and allergen information on FDA-regulated packaged foods in the United States. About this guide ## Prepared by Joy Health {#about-title} Joy Health is an educational publisher, not a medical practice. The reference-reading sequence is Joy Health interpretation checked against the claim-source record. No external clinical reviewer participated. [Read our editorial standards](https://joyhealth.cc/standards) > **Medical information notice:** Joy Health offers general education, not medical advice, diagnosis, or treatment. Seek qualified care for personal medical questions and urgent help for emergencies.