Is Milk More Hydrating Than Water?


Kurt Olsen

Want to remain hydrated but dislike drinking simple water throughout the day? You are certainly not alone. Getting the recommended eight (ish) glasses of water daily can feel like a chore, but there are alternatives to plain water. Other hydrating fluids and water-dense foods can help quench your thirst and help you meet your body’s daily water needs while providing a delicious variety.

While you cannot wholly supplant water with another beverage, you can undoubtedly benefit from the water content in other beverages and foods throughout the day. You may be astonished that milk is hydrating, but you likely have some in your refrigerator.

In addition to its nutritional value, this coffee additive and cereal complement is renowned for its hydrating properties. In fact, scientific evidence suggests that milk is even more hydrating than plain water. Here, we examine the available research to determine whether milk is more hydrating than water, which form of milk (cow’s or plant-based?) is the most hydrating, and what the experts say.

According to the research, milk is hydrating.

Milk is indeed an excellent source of hydration. A study published in The American Journal of Clinical Nutrition in March 2016 compared the effects of various beverages on participants’ fluid balances, including skim milk, whole milk, cola, diet cola, hot tea, iced tea, coffee, lager, orange juice, sparkling water, and a sports drink, and then compared the results to plain water. The results indicated that skim and whole milk are more hydrating than ordinary water, as participants could retain more fluids after drinking milk than after drinking water.

Similar findings have been found in later investigations. For instance, research conducted in May 2020 and published in the journal Nutrients discovered that drinks containing milk were better than water in maintaining fluid levels after intake. In fact, it was shown that milk has hydrating effects that are far more important than water.

In both studies, researchers discovered milk is associated with lower urine output (less frequent urination and less fluid loss) than water. If you consume milk and do not need to defecate directly, this indicates that its hydrating effects last longer. Urinating is fine, and you should do so multiple times daily; however, voiding your bladder immediately after consuming liquids is not always advisable.

“Milk is approximately 90 percent water, so it can be a good source of hydration, especially during the summer when people are more susceptible to dehydration,” confirms clinical dietitian Patricia Kolesa, R.D.3 It also contains sodium and potassium, the electrolytes necessary to replenish what we lose through sweat.

What Makes Milk So Hydrating?

Milk contains key nutrients, including electrolytes.

Milk is exceptionally hydrating for several reasons, the first being that it is not water. Okay, that sounds completely counterintuitive, but let me explain why this is significant: Water contains neither calories nor nutrients. Depending on the variety of water, it may serve as a minor source of a few minerals. Comparatively, milk is rich in water and hydration-enhancing nutrients. It contains a balance of carbohydrates, lipids, protein, vitamins, and minerals and is higher in calories. The longer it takes the body to ingest and metabolize fluids, the longer they are retained.

The research also indicates that milk contains electrolytes. Milk can provide varying quantities of sodium, potassium, and calcium, enhancing the body’s ability to assimilate water and improving hydration levels. Due to its electrolyte content, milk can be a more hydrating beverage option than simple water, according to registered dietitian nutritionist Sarah Schlichter, MPH, RDN.

Electrolytes’ significance in hydration is not novel. Electrolytes are vital minerals responsible for maintaining the body’s fluid balance. They do not provide hydration, but they help your body optimize the efficacy of your fluids so that you remain adequately hydrated for longer. The electrolytes in milk are particularly beneficial following intense exercise. Electrolytes are lost through sweat, so milk is an excellent replenishment method.

Are Non-Dairy, Plant-Based Milks as Hydrating?

People avoid cow’s milk for various reasons, including a vegan lifestyle, allergies, intolerance, and personal preference. Almond, soy, and oat milk are among the most popular plant-based beverages. Each option has been compared to milk for a long time, and each has its pros and cons (for more information, see this helpful non-dairy milk explanation).

However, do non-dairy alternatives such as almond and oat milk possess the same hydrating properties as bovine milk? The answer to that question is yes, at least to some degree.

Non-dairy alternatives have a high water content, but don’t always offer as many replenishing nutrients.

According to registered dietitian Tia Glover, R.D., “non-dairy milk alternatives also tend to contain higher percentages of water,” giving plant-based milk an edge regarding hydration. Soy milk contains approximately 92 percent water, oat milk roughly 91 percent, and almond milk about 97 percent.”456 In comparison, nonfat (skim) cow’s milk contains approximately 91 percent water, and whole cow’s milk contains roughly 88 percent water.37

However, as previously stated, water content is not the only indicator of a food’s hydrating properties; nutritional composition is also significant. Milk is an excellent source of electrolytes, carbohydrates, protein, and lipids that promote hydration. Plant-based milk may also contain these nutrients, but to obtain comparable hydration results, you must research and select a non-dairy alternative fortified with the same nutritional properties as cow’s milk.

According to registered dietitian Samantha Cassetty, R.D., M.S., all milk are comparable in its fluid content. “For example, [a serving of] almond milk contains approximately 8 ounces of water, the same quantity as 1 percent. Almond milk lacks the protein and carbohydrates found in milk, so it may not help you retain as much fluid, but it still contributes to your overall hydration. Cassetty adds that many milk substitutes can be deceptive sources of added sugar, so read labels carefully and strive to remain within (or below!) the American Heart Association’s recommended sugar limits (approximately 36 grams for men and 25 grams for women).

The potential hydrating effects of plant-based milk have yet to be as thoroughly investigated as those of cow’s milk. We know that non-dairy milk primarily comprises water (and contributes to daily hydration). We are still determining if it is as effective as cow’s milk at assisting the body in assimilating, distributing, and retaining water.

When Should You Hydrate With Milk Instead of Water?

Armed with this information, you may be wondering if it’s best to drink milk instead of water to remain hydrated in the future or if there are times when milk is preferable. After humid, vigorous exercise, when you need to replace the calories, electrolytes, and macronutrients (protein, fat, and carbohydrate) that milk contains but lacks, milk is likely a better choice than water.

Endocrinologist and diabetes expert Luis Casaubon, M.D., ECNU, suggests that milk may be preferable for those rehabilitating from an intensive exercise regimen. “Because it has both protein and carbs, it is an ideal choice for a beverage to have after working out. Additionally, milk can help reduce muscle fatigue following intense exercise.”

The Bottom Line:

However, water continues to be the most effective hydrator overall.

“Milk is good for hydration, but water is a better option simply for hydration,” says Dr. Casaubon. He states that water is often the better choice for those with diabetes or whose doctor has suggested a reduced-caloric diet, given that milk may be heavy in calories and carbs.

In the end, milk is an efficient hydrator, and it’s fantastic to know that the milk you pour over your cereal, splash in your coffee, or drink on its own helps to the healthy hydration your body needs regularly. However, milk is not a suitable replacement for water on its own. After strenuous exercise or a long day of trekking, milk is an excellent alternative to water for rehydrating your body since it contains more protein. Aside from that, nothing can compete with water!


What is the most hydrating beverage?

Because it does not include sugar, calories, or caffeine, drinking water is your most excellent option for maintaining proper hydration daily. The fluid you take during the day is primarily determined by the foods and drinks you consume.

Is it OK to hydrate with milk?

Because it contains both electrolytes and carbohydrates, cow’s milk may be a practical choice for rehydration when used as a beverage. As a result of its high protein content, it is an excellent choice as a beverage to consume after physical activity.

What drink is more hydrating than water?

Following “oral rehydration,” beverages like Pedialyte and skim milk came in first. Next came full-fat milk, orange juice, soda, diet soda, cold tea, tea, sports drinks, still water, sparkling water, lager, and coffee.

Water Is Not the Most Hydrating Drink After All, Study Says

Can I drink milk instead of water?

Absolutely. Because water makes up most of the milk, it may be used to rehydrate just as well as any other beverage. However, most nutritionists agree that an adult must consume far more milk than is healthy to receive enough water from dairy alone to fulfill all of their daily hydration requirements.

What drink hydrates you the fastest?

Water. Water is the most excellent and cheapest method to remain hydrated and rehydrate, which is probably no surprise. Unlike many other drinks, water has no added sugars or calories, making it an excellent choice for rehydration after exercise or any additional time of the day.

How can I hydrate without water?

  • Hydration Helpers
  • Start your day with oatmeal.
  • Include more moo.
  • Try carb alternatives.
  • Sip smoothies.
  • Pack your plate with vegetables.
  • Slurp soup.
  • Freeze your fruit.

Is milk the most hydrating drink?

Milk’s diuretic effects meant that the trial participants retained more fluids than they would have with water or Powerade, a sports drink. Therefore, milk was thought to be a more effective means of hydration.

Is milk basically water?

Milk is approximately 87 percent water and 13 percent solids. As it comes from the cow, the solids portion of milk contains approximately 3.7 percent fat and 9 percent solids-not-fat. Milkfat carries the fat soluble vitamins A, D, E, and K.

Contact Us

For more information or to make comments and suggestions, please contact:
Kurt Olsen
Dairy Development Coordinator, Missouri Department of Agriculture
Phone: (573) 291-5704
E-mail: [email protected]