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Measured against water

Does orange juice hydrate you?

Hydrates — roughly like water, with sugar attached

Yes. Juice is mostly water, and orange juice is the only fruit drink anyone has measured this way: 1 liter of it left young men holding more fluid two hours later than still water did, a beverage hydration index of 1.39 against water's 1.00. The honest footnote is that the gap disappeared once the researchers corrected for the fact that juice is only about 89% water, and four-hour urine output was not significantly lower than after water either (P = 0.06).1

Orange juice
1.391
2-h index vs water 1.00 (SD 0.64, from the figure)
After correcting for water content
0.241
The advantage that is left, and it is not significant (P=0.11)
Water in 100% orange juice
88.4%2
An 8 fl oz (237 mL) glass carries about 219 mL of water
Sugar in that glass
20.3 g2
Alongside 116 calories and 451 mg of potassium

Last reviewed 19 sourcesWritten from the studies, not from other websites

The measurement

Juice, measured against water

The beverage hydration index is one experiment, not a law of nature. In 2016 a team led by Ronald Maughan gave 72 rested, already-hydrated young men 1 liter of a drink over 30 minutes and then collected every drop of urine for four hours; divide the urine passed after still water by the urine passed after the test drink and you get the index, where above 1.00 means the body held on to more of it at the two-hour mark. Orange juice came out at 1.39, one of only four drinks that beat water — the others were skim milk (1.58), an oral rehydration solution (1.54) and full-fat milk (1.50). Cola, diet cola, a sports drink, hot and cold tea, coffee, lager and sparkling water were all statistically indistinguishable from plain water.

This pageAbove waterNo differenceWater = 1.00
  • Skimmed milk1.58
  • Oral rehydration solution1.54
  • Full-fat milk1.50
  • Orange juice1.39
  • Cola1.23
  • Diet cola1.08
  • Cold black tea1.07
  • Hot black tea1.03
  • Sports drink1.02
  • Still waterreference1.00
  • Lager0.99
  • Sparkling water0.98
  • Coffee (hot, black)0.91

Significance as marked on the paper’s Figure 2: ** P<0.01, * P<0.05 vs waterWhiskers are 1 SD

BHI = urine after still water ÷ urine after the test drink, 2 h after drinking ended. 72 healthy, recreationally active men aged 18-35, rested, fasted overnight and euhydrated. 1 L of each drink over 30 min in four equal portions; urine collected hourly for 4 h after drinking ended. Each man drank still water plus 3 of the 12 other drinks on separate mornings. Cold drinks 4-6 C, hot tea and coffee 60 C.1Funding: Funded by a grant from the European Hydration Institute (EHI). Prof Maughan chairs the EHI Scientific Advisory Board (not the Institute itself); Dr Watson has also received EHI funding.
Show the data table
Two-hour beverage hydration index for every drink tested, with standard deviations and how each was reported
DrinkIndex2 hCorrectedwater contentSDvs watern
Skimmed milkTesco, 0.1% fat1.581.440.60Above water17
Oral rehydration solutionDioralyte, made up with Highland Spring water1.541.500.74Above water17
Full-fat milkTesco, 3.6% fat1.501.320.58Above water17
Orange juiceTesco Everyday Value — corrected 1.24: not different from water (P=0.11)1.391.240.64≈Above water16
ColaCoca-Cola1.231.090.54≈No detected difference17
Diet colaDiet Coke1.081.080.24≈No detected difference16
Cold black teaPG tips1.071.070.59≈No detected difference17
Hot black teaPG tips1.031.030.24≈No detected difference15
Sports drinkPowerade1.020.980.24≈No detected difference17
Still waterHighland Spring1.001.00—Reference drink72
LagerCarling0.990.940.31≈No detected difference17
Sparkling waterHighland Spring0.980.980.20≈No detected difference17
Coffee (hot, black)Nescafe Original instant0.910.900.31≈No detected difference17

≈ marks a standard deviation read from the paper’s figures rather than its text. “Corrected” adjusts each drink for its own water content, which is the fairer comparison and the one that moves orange juice below significance.

What this number is not

  • — About 17 drinkers per test drink against a pooled water arm, so small differences such as coffee vs water cannot be detected.
  • — Rested, already-hydrated young men drinking 1 L in 30 min; the result describes a 2-4 h window, not all-day hydration.
  • — Caffeine at 96-212 mg in these drinks had no effect on net fluid balance. The authors cite a threshold of about 250-300 mg for a measurable diuretic effect (Maughan & Griffin 2003).
  • — The lager's alcohol content was not reported, and no numeric 4-h BHI was reported for any drink.
  • — Nine of the twelve BHI standard deviations, and eight of the twelve means, are only in the figures; they were read from the figure's vector data and match the text values to about 0.01.
  • — The abstract says the BHI was corrected for water content, but the 1.58, 1.54 and 1.50 values are the uncorrected BHI.

The correction that changes the answer

Juice is not 100% water — the carton tested was 89%. Correct each drink for its own water content and orange juice's index falls to 1.24 (SD 0.57, read from the paper's figure): an advantage of 0.24 over water, 95% CI -0.06 to 0.54, which is not statistically significant (P=0.11). The two milks and the oral rehydration solution stayed ahead after the same correction. Cumulative urine across the full four hours was not significantly lower after juice than after water either (P = 0.06). This is the number most articles skip.1

Lemonade and the other juices were never tested

Lemonade has never been through this test, and neither have apple, cranberry, pineapple or grape juice. Thirteen drinks were measured and those five are not among them, so anything you read ranking them by "hydration index" is extrapolation. What we can do for those is show what is actually in the glass, which is the table further down.1

Water, coffee, OJ or milk - which one is the best hydrater? - BBC

BBC · starts at 0:44 · Watch on YouTube

One of the index study's own authors runs a small version of its urine test on camera, and finds orange juice no different from water: the same place this page lands once juice's lower water content is corrected for.1

Where the video goes further than the evidence

It is a TV demonstration with six people per drink and no statistics, the presenter's line that “the more hydrated they are, the more they'll pee” gets this test backwards (less urine means more of the drink was kept), and the point that sugar helps water absorption does not carry over to juice, because higher sugar concentrations reduce water absorption.1,15

Nothing loads from YouTube until you press play.

The rest of the evidence

What the other studies found

One experiment put orange juice on the index. Three others are close enough to read next to it — a reduced-sugar juice drink at rest, a 100% juice after exercise, and the dose-response work underneath both — and none of them used the same protocol, so the numbers are not interchangeable.

  • Rodriguez-Sanchez 20233

    At restUrine outputDifferent protocol

    12 young (24.5 y) and 11 older (63.8 y) men. 1 L over 60 min (250 mL every 15 min); urine for 3 h; no BHI calculated. Macronutrients from labels; electrolytes by flame photometry, with 'mmol' headers that give no volume.

    What each group drank in Rodriguez-Sanchez 2023, and what was measured
    WaterreferenceCumulative urine at 1, 2 and 3 h: young 825, 1082, 1177 g; older 544, 791, 987 g.
    Fruit juice drink (reduced sugar)Tropicana Trop50 (UK)Cumulative urine at 1, 2 and 3 h: young 773, 1009, 1082 g; older 599, 878, 1037 g.
    Sports drinkLucozade Sport (UK)Cumulative urine at 1, 2 and 3 h: young 804, 1034, 1120 g; older 610, 861, 994 g.
    Low-fat (1%) milkCumulative urine at 1, 2 and 3 h: young 635, 822, 956 g; older 625, 851, 978 g. Net fluid balance after milk differed from water in the young men only.

    Milk improved fluid retention in young men but not in older men, who already retained more water.

    • — No BHI reported; ratios of group-mean urine are not individual-level BHI, so none are given.
    • — 60-min drinking, men only, small groups.

  • Juett 20264

    After exerciseFluid retainedDifferent protocol

    17 adults. After exercise, drank 150% of about 2% body mass lost, matched for water volume; 5 h.

    What each group drank in Juett 2026, and what was measured
    100% fruit juiceRaw Hydrate (watermelon, pomegranate, lime)Urine 1266 ± 403 mL; retention 42 ± 12%.
    Glucose sports drinkLucozade SportUrine 1338 ± 361 mL; retention 37 ± 10%.
    WaterreferenceUrine 1394 ± 360 mL; retention 35 ± 11%.

    Urine (P=0.156) and retention (P=0.059) did not differ significantly between drinks. Blood glucose rose less with the juice than with the sports drink.

    • — Post-exercise retention, not BHI; do not plot alongside BHI values.
    • — 12 participants were withdrawn in total, 3 of them with diarrhoea after the juice.
    • — Innate-Essence, the juice maker, co-funded the work; the senior author has PepsiCo research funding.

    Funding: Innovate UK Knowledge Transfer Partnership with Innate-Essence, maker of the juice tested. The senior author has PepsiCo research funding.

  • Maughan 20195

    At restHydration index

    3 separate cohorts of 12 young active men. Double-blind crossover; 1 L of drink; 4-h urine collection; BHI and net fluid balance.

    What each group drank in Maughan 2019, and what was measured
    Sucrose 0, 5, 10 and 20%10% and 20% sucrose gave lower urine output and higher net fluid balance than 0% and 5%.
    Sodium 7, 15, 27 and 52 mmol/L27 and 52 mmol/L gave greater retention and BHI than 7 and 15 mmol/L.
    Caffeine 0-400 mg/LNo effect of caffeine on urine output (p=0.83), and no differences in arginine vasopressin or aldosterone.

    Retention rose with sucrose (10-20%) and sodium (27-52 mmol/L); caffeine up to 400 mg/L had no effect.

    • — Abstract only; no numeric BHI values.
    • — Peden 2024 describes the sucrose result as only the 20% drink raising BHI, which conflicts with this abstract.

How concentrated juice is, measured

  • Orange juice, as tested in the index study

    570 mOsm/kg, measured in the carton the 72 men drank. That is why juice sits in your stomach longer than water does.1

  • Orange juice, pasteurized or from concentrate

    497–716 mOsm/kg across Venezuelan, Polish and Swiss products, measured in three separate laboratories.6,7,8

  • Apple juice, commercial

    369–773 mOsm/kg, from pasteurized to pressed and bottled — the widest spread of anything in the fridge, and at the top of that range hyperosmotic enough to sit in the stomach. Grape juice, below, is more concentrated still.6,8,9,10

  • Pineapple juice

    692 mOsm/kg, squarely in the same hyperosmotic band as orange and apple juice.8

  • Grape juice

    1,088–1,193 mOsm/kg. The highest non-alcoholic value measured in the Swiss survey, and roughly four times blood.6,8

  • Orange squash, diluted

    22 mOsm/kg at 25 mL of squash in 250 mL of water — the lowest of every drink tested in that study, because it is mostly the water you added.9

  • For reference: the isotonic band

    275–295 mOsm/kg is the range used for isotonic drinks and the neighbourhood of blood. Every 100% juice above sits well outside it.7

One number you will see quoted, and why it is not here

You will find 258 mOsm/kg quoted as "fresh apple juice". It isn't. In the original paper that figure is 86 g of apple pulp blended and made up to 240 mL with water — a diluted pulp drink, not 100% juice. We leave it out rather than repeat it.6

Composition

What is actually in a glass

Each variant on one scale, with water as the baseline. Switch the serving to whichever glass you actually drink from.

Serving size

Showing 237 mL · 8 fl oz of each.

Composition of four 100% juices, two fruit drinks, cola and tap water per 237 mL serving, from USDA FoodData Central
DrinkWaterby weightWater in itper servingCaloriesSugarsProteinSodiumPotassiumCalcium
Water, tap (baseline)FDC 271070799.9%237mL8 fl oz0kcal0g0g9mg0mg7mg
Orange juice, 100%FDC 270918888.4%219mL7.4 fl oz116kcal20.3g1.9g5mg451mg27mg
Apple juice, 100%FDC 270932088.2%218mL7.4 fl oz119kcal25.1g0.2g12mg240mg17mg
Pineapple juice, 100%FDC 270932986.4%214mL7.2 fl oz131kcal24.7g0.9g5mg322mg32mg
Grape juice, 100%FDC 270932583.7%207mL7 fl oz163kcal35.3g0.4g15mg124mg20mg
Cranberry juice cocktailFDC 271057986.2%214mL7.2 fl oz134kcal29.4g0g5mg35mg7mg
LemonadeFDC 271057087.9%218mL7.4 fl oz114kcal28.9g0g15mg25mg5mg
Cola (for comparison)FDC 271054189.4%222mL7.5 fl oz104kcal24.7g0g7mg12mg2mg

USDA publishes composition per 100 grams, so each serving is converted through the item's density — about 1.047 g/mL for juice. Those densities come from rounded household portion weights, so treat them as good to a couple of percent, and water mass is shown as millilitres on the basis that 1 g of water is 1 mL. USDA lists a cup of tap water as 240 g, slightly above the 236.6 mL a cup holds, so the baseline row shows plain water as 100% of the glass rather than handing you back more fluid than you poured. Cranberry juice cocktail and lemonade are filed by USDA as fruit drinks rather than 100% juice.2

Which USDA entries these are
  • Water, tap (baseline): Water, tap — FDC 2710707, Food and Nutrient Database for Dietary Studies (FNDDS) 2024-10-31
  • Orange juice, 100%: Orange juice, 100%, canned, bottled or in a carton — FDC 2709188, Food and Nutrient Database for Dietary Studies (FNDDS) 2024-10-31
  • Apple juice, 100%: Apple juice, 100% — FDC 2709320, Food and Nutrient Database for Dietary Studies (FNDDS) 2024-10-31
  • Pineapple juice, 100%: Pineapple juice, 100% — FDC 2709329, Food and Nutrient Database for Dietary Studies (FNDDS) 2024-10-31
  • Grape juice, 100%: Grape juice, 100% — FDC 2709325, Food and Nutrient Database for Dietary Studies (FNDDS) 2024-10-31
  • Cranberry juice cocktail: Cranberry juice drink, with high vitamin C — FDC 2710579, Food and Nutrient Database for Dietary Studies (FNDDS) 2024-10-31
  • Lemonade: Lemonade, fruit juice drink — FDC 2710570, Food and Nutrient Database for Dietary Studies (FNDDS) 2024-10-31
  • Cola (for comparison): Soft drink, cola — FDC 2710541, Food and Nutrient Database for Dietary Studies (FNDDS) 2024-10-31

Your glass

Your glass, counted

Pick a drink and a size to see the water it delivers, what it costs you in calories and sugar, and where it lands against your daily goal.

mL

237 mL · 8 fl oz

mL

68 fl oz. Not sure? The intake calculator works it out from your weight.

237 mL of orange juice, 100% delivers

219mL of water

7.4 fl oz · 88.4% water by weight

Share of your goal10.9%

Counted as volume rather than water content, it is 11.8% of the goal, which is how Water Goose logs it: the whole glass, with no hydration multiplier. The guidance is making a narrower point: NASEM counts the water a drink carries toward your total intake, and the NHS counts juice toward your fluid while capping it at 150 mL a day.12,11

Calories
116kcal
Sugars
20.3g
Protein
1.9g
Sodium
5mg
Potassium
451mg
Calcium
27mg

In Water Goose this logs as Juice at full volume — and lemonade has its own Lemonade preset, counted the same way. The app counts the whole glass toward your goal: no multipliers, no hydration scores. The science lives on this page; the logging stays simple.

Composition from USDA FoodData Central, converted through each drink’s density.2 Work out your daily goal

Mechanism

Why it holds water (or doesn't)

Juice is not doing anything exotic. It is mostly water, which does most of the work; what is dissolved in the rest decides how fast that water reaches you, and how much of it your kidneys send straight back out.

  • Moderate evidenceRandomised trial

    Orange juice had a higher 2-h beverage hydration index than still water, but after correcting for its lower water content the difference was no longer significant, and its 4-h urine was not significantly lower than water's.1

    Uncorrected 2-h mean differences vs water: orange juice 0.39 (95% CI 0.05-0.73); full-fat milk 0.50 (0.20-0.80); skimmed milk 0.58 (0.28-0.89); ORS 0.54 (0.16-0.93). Corrected for water content: full-fat milk 0.32 (0.06-0.58, P=0.02); skimmed milk 0.44 (0.16-0.72, P<0.01); ORS 0.50 (0.13-0.87, P=0.01); orange juice 0.24 (-0.06 to 0.54, P=0.11). 4-h cumulative urine after orange juice was not significantly lower than water (P=0.06).

    Caveat: The 0.39, 0.50, 0.58 and 0.54 figures are uncorrected values, despite the abstract describing the index as corrected for water content.

  • Moderate evidenceRandomised trial

    Measured composition of 13 common drinks shows the sugary ones are far more concentrated than milk or the sports drink, which sit near the osmolality of the participants' own blood.1

    Osmolality in mmol/kg, Na and K in mmol/L: still water 2 (Na 0); sparkling water 7 (Na 1); cola 432 (carbohydrate 10.6 g/100 mL, Na 2, caffeine 96 mg/L); diet cola 23 (caffeine 127 mg/L); sports drink 297 (3.9 g/100 mL, Na 21, K 4); ORS 229 (1.8 g/100 mL, Na 55, K 20); orange juice 570 (10.5 g/100 mL, Na 1, K 33); lager 774 (2.2 g/100 mL); coffee 34 (caffeine 212 mg/L); hot tea 16 and cold tea 18 (caffeine 179 mg/L); full-fat milk 286 (Na 18, K 41); skimmed milk 282 (Na 19, K 40). Participants' baseline serum osmolality was 293 (6) mmol/kg.

    Caveat: Single UK commercial products from 2014; brands vary. The 275-295 mOsm/kg range often attached to this table is not in the paper: it comes from Sadowska 2017.

  • Moderate evidenceRandomised trial

    Both carbohydrate content and osmolality slow how fast a drink leaves the stomach, and carbohydrate content matters more. A concentrated glucose drink took several times longer to empty than a dilute one.13

    600 mL test drinks, n=6. Half-emptying time: 40 g/L glucose (230 mosmol/kg) 17 ± 1 min; 40 g/L glucose polymer (42 mosmol/kg) 14 ± 1 min; 188 g/L glucose polymer (237 mosmol/kg) 64 ± 8 min; 188 g/L glucose (1300 mosmol/kg) 130 ± 18 min. Values are mean ± SEM.

    Caveat: Abstract only. 188 g/L is about 18.8% carbohydrate, roughly twice a typical cola.

  • Moderate evidenceRandomised trial

    After exercise, a hypertonic 10% glucose drink left much more fluid sitting in the stomach than a 2% drink, which explains part of its lower early urine output.14

    n=8, about 1.8% body mass lost, drank 150% of the loss. At 120 min, 0.3% of the 2% drink and 42.1% of the 10% drink remained in the stomach (p<.001). Retained at 240 min 52% vs 64%. Once gastric residue was accounted for, net fluid balance was better with the 2% drink at 60 and 120 min.

    Caveat: Abstract only.

  • Moderate evidenceSystematic review

    Pooled human intestinal perfusion studies found that higher carbohydrate concentration reduces water absorption, and that mixing carbohydrate types helps by lowering osmolality in the gut.15

    30 triple-lumen perfusion reports since the early 1960s; the abstract gives no single numeric threshold.

    Caveat: Abstract only. The second author was affiliated with the Gatorade Sports Science Institute, PepsiCo.

  • Weak evidenceOther

    Commercial grapefruit, orange and apple juices were all strongly hyperosmotic, and in rats water moved into the gut as juice osmolality rose.10

    Grapefruit juice 552, orange juice 686 and apple juice 749 mOsm/kg; in rat ileum, fluid volume ranked apple > orange > grapefruit > purified water.

    Caveat: Abstract only. The gut data come from rats; the juice osmolality values were measured directly.

The honest part

When water is still the better pick

Nothing above makes juice a hydration drink. It makes it a food that happens to be 88.4% water. Here is where water is still the better pick.

  • The trade-off is sugar, and it is not small

    An 8 fl oz (237 mL) glass of orange juice carries 20.3 g of sugar and 116 calories; grape juice 35.3 g; cranberry juice cocktail 29.4 g; lemonade 28.9 g. For scale, the same glass of cola has 24.7 g. Juice brings potassium and vitamin C that cola does not — but a liter of it carries about 86 g of sugar. Water gets you the same fluid at zero.2

  • “100% juice” and “juice drink” are different products

    USDA files cranberry juice cocktail and lemonade under fruit drinks rather than juice: the cocktail is 86.2% water with 29.4 g of sugar a glass and only 35 mg of potassium, because most of what is in it is water and added sugar. Lemonade is the same idea — water, lemon and sugar, 25 mg of potassium a glass. Neither has been measured on the hydration index. Read the front of the carton: "100% juice" is a regulated phrase, and "juice drink", "cocktail" and "-ade" are not the same thing.2

  • On quantity, the guidance is about the sugar

    The NHS is the clearest of the authorities: it counts juice and smoothies toward your fluid but caps them at 150 mL a day, taken with a meal. The CDC says daily intake comes mostly from water and other drinks, and that sugary drinks carry calories with little nutritional value. Neither is arguing that the water in juice does not count — both are arguing about what comes with it.11,16

Who should be careful

  • If you have been told to limit potassium or fluid

    Kidney disease and some heart conditions come with those limits, and an 8 fl oz glass of orange juice carries about 451 mg of potassium. Follow your clinician's numbers, not ours.2

  • If you are watching blood sugar

    Juice delivers its sugar fast and without the fiber of whole fruit. What that means for you is a conversation with your clinician, not something this page can answer.

  • After hard exercise

    Large volumes of juice can upset your gut: in the 2026 post-exercise trial, 3 people withdrew with diarrhea after the juice arm — 12 participants were withdrawn in all, on top of the 17 who finished. Water or a sodium-containing drink is the safer bet for big replacement volumes.4

  • For children

    The water comes with the same sugar. We give no age-specific amounts here — paediatric guidance belongs with your paediatrician.

Labels

What the labels say

Published panels for products people actually buy. These are label values for one flavour and package, not laboratory measurements, and none of the brands here had any involvement in this page.

Published nutrition panels for branded products, per the serving each label states
ProductServingCaloriesSugarsProteinSodiumPotassium
Tropicana17Pure Premium Orange Juice, Original (No Pulp)8 fl oz (240 mL)11022 g2 g0 mg450 mg
Crystal Light18Lemonade powdered drink mix (pitcher packets)1/5 packet (3 g) made up per the directions (about 12.8 fl oz)50 g0 g55 mg100 mg

Labels checked 2026-09-15. A dash means the label does not publish that value — it is not a zero. Formulations and panels change, so treat these as a snapshot and check the carton in your hand.

  • Tropicana: 0 g added sugars; 100% orange juice; vitamin C 90 mg.
  • Tropicana: Nutrition record dated 3 October 2022.
  • Crystal Light: One packet makes 2 quarts (8 cups) and about 5 servings; the brand's own calorie claim uses a 12 fl oz drink.
  • Crystal Light: Sweetened with aspartame and acesulfame potassium; contains soy.
The two rows say the whole thing out loud. Squeezed oranges in a carton: 110 calories and 22 g of sugar a glass, with 450 mg of potassium. Powdered lemonade: 5 calories, no sugar, and the fluid is whatever water you mixed it into. If what you want from lemonade is the fluid, that is the version that gives you the fluid and nothing else.17,18

Questions

Juice and hydration, question by question

Does orange juice hydrate you as well as water?

Slightly better, for a couple of hours, in the one study that measured it — and the advantage does not survive scrutiny. Orange juice scored 1.39 on the beverage hydration index against water's 1.00 at two hours. Correct for the fact that it is 89% water rather than 100% and the difference shrinks to 0.24 and is no longer statistically significant (P = 0.11); across four hours, urine output was not significantly lower than after water either (P = 0.06). Treat juice as a drink that hydrates about like water and brings 20 g of sugar per glass with it.1,2

Is lemonade hydrating?

Yes, in the plain sense: lemonade is 88% water, so an 8 fl oz glass delivers about 218 mL of fluid. Nobody has measured lemonade on a hydration index, so any ranking you see is guesswork. What is measured is the sugar — 29 g in that same glass, more than the 25 g in a glass of cola. A powdered sugar-free mix is a different drink: 5 calories and no sugar, with the fluid coming from the water you mixed it into.2,18

Is apple juice hydrating?

It is 88% water, so an 8 fl oz glass gives you about 218 mL of fluid along with 25 g of sugar and 240 mg of potassium. Apple juice has never been on the hydration index, so there is no measured comparison with water. It is one of the most concentrated things in your fridge: commercial apple juices measure 369–773 mOsm/kg against blood's isotonic band of roughly 275–295. That concentration is why it leaves the stomach slowly.2,6,8,9,10,7,13

Is cranberry juice hydrating?

The fluid is real — 86% water, about 214 mL per 8 fl oz glass. But the thing most people buy is cranberry juice cocktail, which USDA classifies as a fruit drink: 29 g of sugar per glass and only 35 mg of potassium, because it is largely water and added sugar. No one has measured it on the hydration index. We have nothing to say here about urinary tract infections; that is a medical question for a clinician, not a hydration one.2

Is pineapple juice hydrating?

Yes, in the same ordinary way: 86% water, about 214 mL of fluid per 8 fl oz, with 25 g of sugar and 322 mg of potassium. It has not been tested on the hydration index. Measured for concentration, pineapple juice came in at 692 mOsm/kg — firmly in the same hyperosmotic band as orange and apple juice.2,8

Which juice is the most hydrating?

Nobody can answer this from measurement, because only orange juice has been through the index. What you can compare is what is in the glass. Per 8 fl oz, orange juice delivers the most water (219 mL) with the most potassium (451 mg) and the least sugar of the 100% juices (20.3 g); grape juice delivers the least water (207 mL) with the most sugar (35.3 g). On that basis orange juice is the sensible pick — and water beats all of them at 237 mL and no sugar.1,2

Can I drink orange juice instead of water?

For fluid, a glass of juice does most of what a glass of water does. As a swap for all your water it stops being a hydration question and becomes a sugar question: 2 liters of orange juice a day is about 171 g of sugar and 984 calories, and it still delivers only about 1,850 mL of actual water. The NHS counts juice toward your fluid but caps it at 150 mL a day with a meal. Use juice as one of your drinks, not as your water.1,2,11

Does juice count toward your daily water intake?

Yes. Every authority that defines total water intake counts all beverages plus the water in food: NASEM sets adequate intakes of 3.7 L a day for men and 2.7 L for women on exactly that basis, with about 20% of it coming from food. The CDC says the same in plainer language. In children, fruit and vegetable juice measurably tracked with better hydration status — about 10% of their total water intake came from juices. Water Goose counts juice at full volume for the same reason.12,16,19

Receipts

Sources and how we compiled this

Where the composition comes from

U.S. Department of Agriculture, Agricultural Research Service. FoodData Central. Built 2026-09-15 from the published CSV releases, never hand-typed.

  • Food and Nutrient Database for Dietary Studies (FNDDS) · 2024-10-31
  • — Drinks and prepared foods use FNDDS (foods and drinks as consumed) whenever FNDDS has a code for the item.
  • — Raw produce and dairy foods use Foundation Foods when the entry is current (listed in foundation_food.csv), stands for the food generally rather than one cultivar or colour, and reports water, energy and potassium, plus fiber for plant foods. Otherwise SR Legacy.
  • — A Foundation pick with no household portions uses the portions of the SR Legacy entry for the same food (portionsSource).
  • — Fluid milks use FNDDS, whose composition matches the Foundation analyses (crossCheck) and which has consistent drink portions.
  • — SR Legacy fills any remaining gap. No proxy is used where USDA has no sensible entry (see missing).

What this evidence cannot tell you

  • — The Beverage Hydration Index measures short-term retention, not 24-h hydration: for each person it is urine after still water divided by urine after the test drink, anchored 2 h after drinking 1 L over 30 min.
  • — Most participants were young, healthy, euhydrated, fasted, rested men given a single 1 L dose. Older adults retain more water and respond differently.
  • — Post-exercise retention percentages come from dehydrated people drinking 100-150% of the body mass they lost. They are not comparable to BHI values and must not share a scale with them.
  • — Clarke 2019 reports mean ± SEM while most studies report SD, so spreads are not directly comparable.
  • — No resting BHI data were found for soup, smoothie, lemonade or coconut water. Energy-drink evidence comes from one modified-protocol study, and soda evidence is cola and diet cola from Maughan 2016 only.
  • — Many of these studies are industry funded: the European Hydration Institute, Entrinsic, Dairy Management, Nuun, Coca-Cola, Buoy, Lingtea, QCK, the Almond Board, 8 POiNT, VitaCoco, Liquid I.V., Innate-Essence and ITO EN all appear as funders.
  • — Commercial formulations change over time. Compositions are as measured or labelled at the time of each study and are not current labels.

Who paid for the research

Hydration research is heavily industry funded. That does not make a study wrong, but you should know who paid before you weigh it. Water Goose took no money from anyone named here, and no brand saw this page before it went up.

  • — Maughan 2016: Funded by a grant from the European Hydration Institute (EHI). Prof Maughan chairs the EHI Scientific Advisory Board (not the Institute itself); Dr Watson has also received EHI funding.
  • — Juett 2026: Innovate UK Knowledge Transfer Partnership with Innate-Essence, maker of the juice tested. The senior author has PepsiCo research funding.
  • — Shi & Passe 2010: Second author affiliated with the Gatorade Sports Science Institute, PepsiCo Inc.

References

Every number on this page points at one of these. Product labels were checked 2026-09-15.

  1. 1

    Maughan RJ, Watson P, Cordery PAA, Walsh NP, Oliver SJ, Dolci A, Rodriguez-Sanchez N, Galloway SDR. A randomized trial to assess the potential of different beverages to affect hydration status: development of a beverage hydration index. Am J Clin Nutr 2016;103(3):717-723.

    StudyRead: full textOpen source

    Funding: Funded by a grant from the European Hydration Institute (EHI). Prof Maughan chairs the EHI Scientific Advisory Board (not the Institute itself); Dr Watson has also received EHI funding.

    Read from the LJMU green open-access accepted manuscript (https://researchonline.ljmu.ac.uk/id/eprint/12468/); the publisher page was blocked. ISRCTN13014105.

  2. 2

    U.S. Department of Agriculture, Agricultural Research Service. FoodData Central (SR Legacy and Foundation Foods).

    DatasetRead: official pageOpen source

    Water content is not the same thing as a net hydration effect.

  3. 3

    Rodriguez-Sanchez N, Galloway SDR. A randomised trial to assess fluid and electrolyte balance responses following ingestion of different beverages in young and older men. Eur J Appl Physiol 2023;123(10):2331-2340.

    StudyRead: full textOpen source

    Same urine protocol as the BHI, but drinks taken over 60 min and no BHI calculated.

  4. 4

    Juett LA, van der Wolf-Ong J, Gyamfi PA, et al. Post-exercise rehydration: a randomized cross-over trial comparing a 100% fruit juice, a glucose-based sports drink, and water. J Int Soc Sports Nutr 2026;23(1):2721140.

    StudyRead: full textOpen source

    Funding: Innovate UK Knowledge Transfer Partnership with Innate-Essence, maker of the juice tested. The senior author has PepsiCo research funding.

    The juice was Raw Hydrate (watermelon, pomegranate and lime), not orange juice; the sports drink was Lucozade Sport.

  5. 5

    Maughan RJ, Watson P, Cordery PAA, Walsh NP, Oliver SJ, Dolci A, Rodriguez-Sanchez N, Galloway SDR. Sucrose and sodium but not caffeine content influence the retention of beverages in humans under euhydrated conditions. Int J Sport Nutr Exerc Metab 2019;29(1):51-60.

    StudyRead: abstractOpen source

    Abstract describes a double-blind crossover design. Numeric BHI values are not in the abstract. Peden 2024 describes the sucrose result differently (only the 20% drink raising BHI).

  6. 6

    Dini E, De Abreu J, López E. Osmolalidad de bebidas de consumo frecuente [Osmolality of frequently consumed beverages]. Invest Clin 2004;45(4):323-335.

    StudyRead: full textOpen source

    Venezuelan products, 2002-2003; vapour-pressure osmometer. Its 'natural' fruit drinks are lab blends of pulp diluted with water, not 100% juice (only the orange juice was undiluted).

  7. 7

    Sadowska A, Świderski F, Rakowska R, Waszkiewicz-Robak B, Żebrowska-Krasuska M, Dybkowska E. Beverage osmolality as a marker for maintaining appropriate body hydration. Rocz Panstw Zakl Hig 2017;68(2):167-173.

    StudyRead: full textOpen source

    Polish market products. This is the source of the 275-295 mOsm/kg range (it describes the isotonic drinks tested), not Maughan 2016.

  8. 8

    Mettler S, Rusch C, Colombani PC. Osmolality and pH of sport and other drinks available in Switzerland. Schweiz Z Sportmed Sporttraumatol 2006;54(3):92-95.

    StudyRead: full textOpen source

    Products bought November 2005; freezing-point osmometer, duplicate readings.

  9. 9

    Martir J, Flanagan T, Mann J, Fotaki N. Impact of Food and Drink Administration Vehicles on Paediatric Formulation Performance: Part 1. AAPS PharmSciTech 2020;21(5):177.

    StudyRead: full textOpen source

  10. 10

    Takemura M, Inoue K, Tamai I, Shirasaka Y. Magnitude of Fruit Juice-Drug Interactions Due to Osmolality-Dependent Fluid Secretion. Biol Pharm Bull 2024;47(1):72-78.

    StudyRead: abstractOpen source

  11. 11

    NHS. Water, drinks and your health.

    GuidelineRead: official pageOpen source

    Page last reviewed 17 May 2023; next review was due 17 May 2026, so the review is overdue as of September 2026.

  12. 12

    Institute of Medicine. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate. Chapter 4: Water. Washington, DC: The National Academies Press; 2005.

    GuidelineRead: full textOpen source

    Cite this directly for adequate intakes: Maughan 2016's introduction misstates the women's figure. On alcohol it concludes the diuresis is transient; it makes no explicit 'all drinks count equally' statement.

  13. 13

    Vist GE, Maughan RJ. The effect of osmolality and carbohydrate content on the rate of gastric emptying of liquids in man. J Physiol 1995;486(Pt 2):523-531.

    StudyRead: abstractOpen source

    Values are mean ± SEM.

  14. 14

    Clayton DJ, Evans GH, James LJ. Effect of drink carbohydrate content on postexercise gastric emptying, rehydration, and the calculation of net fluid balance. Int J Sport Nutr Exerc Metab 2014;24(1):79-89.

    StudyRead: abstractOpen source

  15. 15

    Shi X, Passe DH. Water and solute absorption from carbohydrate-electrolyte solutions in the human proximal small intestine: a review and statistical analysis. Int J Sport Nutr Exerc Metab 2010;20(5):427-442.

    StudyRead: abstractOpen source

    Funding: Second author affiliated with the Gatorade Sports Science Institute, PepsiCo Inc.

  16. 16

    Centers for Disease Control and Prevention. Water and Healthier Drinks. Last reviewed 5 March 2026.

    GuidelineRead: official pageOpen source

    Read through a summarising fetch tool; do a verbatim check before quoting its wording.

  17. 17

    Tropicana. Pure Premium Original (No Pulp), nutrition facts (record updated 3 October 2022).

    Product labelRead: official pageOpen source

  18. 18

    Kraft Heinz. Crystal Light Lemonade powdered drink mix (pitcher packets), nutritional facts.

    Product labelRead: official pageOpen source

  19. 19

    Montenegro-Bethancourt G, Johner SA, Remer T. Contribution of fruit and vegetable intake to hydration status in schoolchildren. Am J Clin Nutr 2013;98(4):1103-1112.

    StudyRead: abstractOpen source

How we compiled this

Hydration results are limited to studies that measured urine output or fluid retention against a water control. Only one has ever tested orange juice, so we show its correction and its caveats rather than its headline alone, and apple, cranberry, pineapple, grape and lemonade get no hydration index because nobody has measured one. Osmolality figures are measured values from five separate laboratories. Brand figures are from official label pages, checked 2026-09-15. Nobody paid for this page, and no brand reviewed it.1,6,8,7,9,10,17

This page describes what studies measured in healthy adults. It is general wellness information, not medical advice, diagnosis or treatment. Fluid needs change with health conditions, medication and pregnancy — and some conditions require drinking less. Talk to a clinician about yours.

Keep the number

That glass was 219 mL of actual water and 20 g of sugar — and the number is gone the moment this tab closes. Water Goose keeps the running total, juice and lemonade included, counted at full volume.

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