Does it count?

Does milk count as water?

Quick answer

Milk contributes to beverage intake. BHI research measured short-term urine output after 1 L in 72 healthy, hydrated men. It does not convert drinks into effective millilitres or show long-term health benefit. Milk retained more fluid in that experiment; alcohol is not a hydration strategy.

Maintained by the WaterDailyGoal TeamLast updated Editorial update; not a medical review.

The short answer

Counts as a beverage

Counts as a beverage; short-term retention is a separate research measure.

BHI research measured short-term urine output after 1 L in 72 healthy, hydrated men. It does not convert drinks into effective millilitres or show long-term health benefit. Milk retained more fluid in that experiment; alcohol is not a hydration strategy.

Composition and caffeine vary by product and preparation. Check the label. The table records beverage volume, not absorbed water.
ServingmlThe short answer
1 glass (240 ml)240 mlCounts as a beverage; short-term retention is a separate research measure.
1 cup (240 ml) (Does coffee count as water)240 mlCoffee hydrates about as well as water for habitual drinkers.
1 mug (240 ml) (Does tea count as water)240 mlTea is nearly all water and hydrates well.
1 can (355 ml) (Does soda count as water)355 mlCounts as fluid, but the sugar makes it a poor hydrator.

The bottom line

Count the volume you drink; do not add a BHI bonus. Choose a product that fits your nutritional needs and tolerances.

Whatever drinks you choose, the goal is the same: hit your total daily fluid target, mostly from water. Use the calculator to find that number for your body.

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Frequently asked

Is milk more hydrating than water?

BHI research measured short-term urine output after 1 L in 72 healthy, hydrated men. It does not convert drinks into effective millilitres or show long-term health benefit. Milk retained more fluid in that experiment; alcohol is not a hydration strategy.

Does plant milk hydrate you the same way?

Plant-based drinks contribute fluid, but their ingredients and fortification vary. The cited dairy-milk trial does not establish a hydration ranking for all plant-based products. Check the product label.

Should I count milk toward my water goal?

Yes, you can count it. A glass of milk is roughly 210 ml of water. If you drink several glasses a day, they genuinely add up — just remember milk also brings calories and protein, unlike plain water.

Sources

  • 1.Maughan et al., Beverage Hydration Index, AJCN 2016A controlled short-term study in 72 healthy, hydrated men compared urine output after 1 L of different drinks. Milk and ORS showed greater short-term retention; BHI is not a conversion to effective beverage volume or proof of long-term benefit.AJCN 103(3):717–723; abstract, methods and results (2-hour BHI and 4-hour cumulative urine)
  • 2.U.S. National Academies (IOM/NAM), 2005Adequate total water intake of about 3.7 L/day for men and 2.7 L/day for women, including water from food and all beverages.Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate, Summary: water adequate intakes; drinks and food