If you’re searching for a protein powder, it’s easy to get overwhelmed. There’s a ton of choices.

One of the lesser-known options is milk protein isolate. It’s a type of protein that’s derived from — you guessed it — milk. This type of protein is high in nutrients and might even offer several health benefits. Here’s how to decide if this protein deserves a spot in your supplement regimen.

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Milk protein isolate (MPI) is a type of protein-rich powder made from skim milk. Because it has so much protein for its weight, it’s considered a concentrated milk protein product.

What kind of protein are we talking about? The casein to whey ratio of MPI is 80-to-20. That’s similar to fresh milk. Because it’s so high in casein, MPI takes longer to digest than products richer in whey protein. Casein’s considered a “slow protein” because it provides a steady release of amino acids (the building blocks of protein) over several hours.

MPI contains 90 percent or more protein by weight. All (or most) of the lactose, which is a sugar found in milk, is removed during processing. It’s super low in fat (usually less than 3 percent by weight) and low in carbs. It’s typically added to food products like snack bars to boost protein content. You can take it on its own, too, as a nutritional supplement.

Protein isn’t the only thing MPI has going on. It also contains a variety of important nutrients. Here’s the nutrition breakdown for a 27 gram serving of a whey and milk protein isolate protein powder.

  • Calories: 100
  • Protein: 23 grams
  • Fat: 0 grams
  • Carbs: 0 grams
  • Calcium: 20% of the Daily Value (DV)

As you can see, MPI is super high in protein and low in fat and carbs.

It’s also a great source of calcium. You need this mineral for lots of things, including muscle function and cellular communication. It’s is also super important for bone health.

MPI differs from other types of milk-derived protein powders. Here’s how it stacks up to other popular proteins.

Milk protein isolate vs. milk protein concentrates

MPIs have more protein than milk protein concentrates (MPC).

There’s a bunch of different types of MPCs, but even the highest protein MPC (85 percent protein by weight) is lower in protein than MPI (90 percent or more protein by weight).

Milk protein isolate vs. whey protein

Whey protein is a super popular type of protein powder. Unlike MPI, which has both whey and casein, whey protein powder only contains whey.

They have different amounts of nutrients, too. Some whey products are slightly higher in carbs and lower in protein, calories, and calcium than MPI.

Milk protein isolate vs. casein

Casein powders contain only casein, while MPI provides both casein and whey.

Compared to MPI, casein powder is usually slightly lower in protein and higher in carbs.

Like other protein powders, MPI is a smart choice if you need extra protein in your diet, if you’re trying to build muscle, or if you’re searching for a filling protein powder.

If you need to up your protein intake

MPI is an excellent source of absorbable protein.

Adding just one serving of a whey and milk protein isolate powder to your daily smoothie will provide you with a whopping 23 grams of absorbable protein. Plus, MPI is mild in flavor and heat stable. You can add it to a ton of recipes including smoothies, oatmeal, and baked goods.

What are the perks of having enough protein in your diet? It may help you lose weight in a sustainable way, gain and maintain muscle mass, and even improve bone health.

If you’re looking to build muscle mass

MPI can be used to pack on muscle mass.

Adding protein powders to your diet is a convenient way to boost overall protein intake, which can help increase muscle mass over time. (Especially when you combine it with resistance training.)

MPI contains all nine of the essential amino acids your bod needs to perform critical functions like building muscle, including the branched chain amino acids involved in muscle growth and repair. And there’s research to back this up. A 2019 review found that supplementation with milk proteins significantly increased muscle mass in middle-aged and older adults.

Milk proteins that contain both whey and casein may also promote slower, yet prolonged muscle protein synthesis compared to whey protein alone. That’s because whey protein’s digested and absorbed more quickly than casein. Proteins that are higher in casein are digested and absorbed at a slower rate. That can help amino acid release into the bloodstream over a longer period of time.

Studies also suggest that consuming milk protein products that contain both whey and casein (like MPI) are more effective for encouraging muscle growth after resistance exercise than soy protein.

If you want a protein powder that’ll keep you full

Protein is the most filling macronutrient. Adding a protein source to meals and snacks is essential if you want to avoid getting hangry. MPI is high in casein, a milk protein that’s digested and absorbed slowly by the body. This means it’s filling and can keep you feeling satisfied over time.

Studies suggest that, although whey protein seems to be more filling immediately after meals, a combination of casein and whey makes you feel full for an extended time. So, consuming a product that contains both whey and casein is a smart way to keep your bod fueled and satisfied.

But you don’t have to take a protein powder to get this effect. Adding any source of high quality protein to meals and snacks will help.

MPI isn’t appropriate for peeps with an allergy to cow’s milk proteins like casein and whey. This type of allergy is more common in kids. It’s pretty rare in adults.

Also, some research has linked whey protein supplementation with acne. That’s because consuming whey protein can impact hormones like insulin and IGF-1, which may promote acne development or worsen existing acne. If you experience acne, you may want to choose another type of protein, like pea protein, instead.

You can use MPI the same way you would other types of protein powders. Most peeps add it to shakes and smoothies, but you can also try it in yogurt, chia pudding, oats, soups, and a bunch of other recipes.

MPI isn’t as popular as other types of protein like whey protein, though. You may not be able to find it in your local health food or grocery store. You can find MPI online if it’s not available in a store near you.

  • MPI is a type of milk-derived protein that contains both casein and whey.
  • It can help support muscle growth, increase your protein intake, and keep you feeling satiated between meals.
  • If you’re looking for a dairy-based protein powder to help boost your protein consumption, give MPI a try.
  • MPI might be hard to find in your local store, but it’s available online.