Total Water vs Drinking Water: How Much Do You Need to Drink?

Look up a daily water amount and you will meet two numbers from the same US report: 3.7 liters for men, and about 3.0 liters. Both are right. The bigger one counts the water in your food.

Our main guide on how much water you should drink a day covers every official figure. Here you will see which of the two to aim for, and how much your plate can add.

How Much of Your Daily Water Comes From Food?

About a fifth. In the US survey data behind the official values, food supplied about 19 % of the water healthy adults took in and drinks the other 81 %, the US National Academies report. For the average man that is roughly 0.7 liters (24 oz) a day.

Total Water and Drinking Water, Defined

Total water is every drop that enters your body in a day: plain water, every other drink, and the moisture in your food. Drinking water, in these reports, means drinks only, from tap water to coffee.

The Split in Numbers

Those are averages across thousands of people. Your own split depends on what lands on your plate, and it can swing a lot from one day to the next.

A Day of Food, Measured

Here is one summer day built from USDA FoodData Central values. A gram of water is about 1 ml, so grams of water per 100 g of food turn straight into milliliters.

That day gives you about a liter from food, more than the US average. Keep the bread and rice, swap the rest for 30 g of saltine crackers and 30 g of almonds, and your food brings only about 160 ml (5.5 oz).

Does 3.7 Liters a Day Mean I Should Drink 3.7 Liters?

No. The 3.7 liters for men and 2.7 liters for women count the water in your food too: the 2004 report "refers to total water, which includes the water contained in beverages and the moisture in foods." The drinks part is about 3.0 liters (101 oz) for men and 2.2 liters (74 oz) for women.

Do Fruits and Vegetables Count Toward Your Water Intake?

Yes. The US panel counts the water in fruit, vegetables and other foods as part of your total water, and it lists fruits and vegetables beside juice, milk, coffee and tea as everyday sources. Cucumber is about 95 % water by weight and watermelon about 92 %, so a big slice works much like a small drink.

For a ranked list of the wettest foods, and the dry ones that add almost nothing, see foods with the most water. Coffee and tea count as drinks, and does coffee count as water covers what the studies found.

Does Soup Count as Water Intake?

Yes. Canned chicken noodle soup made with water is about 94 % water by weight, close to a drink, per USDA FoodData Central. A 300 g bowl brings about 280 ml (9.5 oz), more than a standard 8 oz cup of water.

On a cold day, when a glass of cold water appeals less, a bowl of soup at lunch does part of the work.

Which Number Should You Aim For?

Aim for the drinks number. It is the part you control and can count, and food then works as a buffer on top.

• Use the drinks figure (about 3.0 L for men, 2.2 L for women) or your own goal from the water intake calculator, which gives a drinks goal for this reason.
• On a day of fruit, soup and salad, you can feel fine a glass short of that goal.
• On a day of bread, crackers and nuts, drink your full goal and an extra glass if your pee runs dark.

Your weight moves the drinks number too, and water intake by weight shows by how much. The most famous drinks number of all has a food story behind it as well: is 8 glasses of water a day enough traces it back to 1945.