Drinking protein shakes is a simple way to increase your protein intake and support muscle building, bone health, and weight loss.
Protein shakes can be made with various ingredients—most commonly milk or water—which can affect their protein content and overall nutritional value.
Should You Mix Protein Powder with Milk or Water?
Whether you mix protein powder with milk or water depends on a few factors, including your health goals and personal taste preferences.
If you’re aiming to keep your shake as low-calorie as possible, water is the better choice since it contains no calories.
If you’re looking to add extra calories and protein to your shake, milk is the way to go. Whole milk contains calories, carbs, fat, and protein. One cup of whole milk has around 149 calories, 11.3 grams of carbs, 7.81 grams of fat, and 7.98 grams of protein. You can also opt for low-fat or skim milk if you want fewer calories and fat.
Some people simply prefer the taste and texture of milk-based shakes. Milk or plant-based milks like almond, coconut, or soy can make the shake creamier, while water creates a thinner consistency with a more neutral flavor.
Finally, if you’re lactose intolerant, you’ll want to choose water or a non-dairy milk alternative instead of regular milk.
Benefits of Mixing Protein Shakes with Water
Water has no calories, making it ideal for those looking to reduce the overall calorie content of their protein shake.
A shake made with water and 30 grams of whey protein powder typically contains around 100 calories and 25 grams of protein. The same shake made with a cup of whole milk jumps to about 249 calories and 32.98 grams of protein.
Besides being lower in calories, water-based shakes are more convenient—easy to mix at the gym, at school, or at work using water from a drinking fountain.
Water is also carb-free, whereas whole milk contains around 11–12 grams of carbs per cup. If you’re following a low-carb diet or looking to better manage blood sugar levels, a water-based shake might be the better choice.
Benefits of Mixing Protein Shakes with Milk
One cup of milk adds about 8 grams of protein to your shake.
Milk contains both whey and casein protein, which support muscle growth. That’s why milk and chocolate milk are popular among people aiming to bulk up.
Milk also provides carbohydrates that help replenish muscle glycogen—your body’s stored form of glucose used during intense workouts.
Post-workout milk consumption may promote muscle growth, reduce soreness, and repair muscle damage—potentially performing as well as or better than some commercial recovery drinks.
Combining milk with whey or plant-based protein powders can support muscle repair and strength gains after exercise. Plus, milk creates a creamier, thicker shake, which many find more satisfying.
Milk Alternatives
If you don’t drink regular milk but want something other than water in your protein shake, plant-based milks like almond or soy milk are good alternatives. They add creaminess and additional nutrients.
For example, soy milk contains around 9 grams of protein per cup—sometimes more than dairy milk. It’s a great option for those on a plant-based diet who still want the protein boost.
Other plant milks like almond or cashew milk are lower in protein but offer a creamy texture to enhance your shake’s taste.
What’s Better for Workouts?
Regardless of whether you use milk or water, drinking protein shakes with added protein powder can help you meet your fitness and body composition goals.
However, for fitness enthusiasts, mixing protein powder with milk might be the better choice. Milk has been shown to help with muscle growth and reduce post-workout soreness and damage.
That said, protein powders like whey or pea protein offer many of the same benefits on their own. So even if you choose water, you’re still getting a highly effective protein supplement.
Other Considerations
When choosing your protein shake base, think about dietary restrictions, taste preferences, and your overall health needs.
If you follow a dairy-free diet, such as a vegan or paleo diet, mix your protein powder with water or a plant-based milk alternative.
Taste also matters—milk or milk alternatives provide a smoother, more flavorful shake. If you’re mixing protein powder with water, consider using a flavored powder to make it more enjoyable.
Lastly, if you have lactose intolerance, allergies, or other health concerns, avoid ingredients like dairy milk or soy that may trigger symptoms. Stick with water or a safer alternative for your body.
