Skip to content
HealthWorld

The Best Whey Isolate Protein Powders

Updated By the HealthWorld editorial teamHow we pick

We may earn a commission when you buy through our links, at no extra cost to you. Affiliate disclosure

As an Amazon Associate I earn from qualifying purchases.

Top picks at a glance

  1. 1
    Dymatize ISO100 Hydrolyzed

    Best overall

    Dymatize ISO100 Hydrolyzed

    Protein 25 g · Type Hydrolyzed isolate

  2. 2
    Isopure Zero Carb Whey Isolate

    Best for low-carb and keto

    Isopure Zero Carb Whey Isolate

    Protein 25 g · Carbs 0 g

  3. 3
    Optimum Nutrition Gold Standard 100% Whey

    Best isolate-led blend

    Optimum Nutrition Gold Standard 100% Whey

    Protein 24 g · BCAAs 5.5 g

Whey isolate is filtered to remove most of the fat, carbs and lactose, leaving a powder that's mostly protein. Dymatize ISO100 is our top pick for its hydrolyzed isolate and 25 g of protein per serving, and Isopure Zero Carb is the pick for low-carb diets. If you don't need a pure isolate, Gold Standard is a blend led by whey isolate.

Our picks

  1. Dymatize ISO100 Hydrolyzed

    #1Best overall

    Dymatize ISO100 Hydrolyzed

    Hydrolyzed whey protein isolate with 25 g of protein per serving and very little fat or sugar. Its light texture is easy to digest for many people.

    Protein 25 gType Hydrolyzed isolateAmazon Full facts →
  2. Isopure Zero Carb Whey Isolate

    #2Best for low-carb and keto

    Isopure Zero Carb Whey Isolate

    100% whey protein isolate with 25 g of protein and 0 g of carbs and sugar per serving.

    Protein 25 gCarbs 0 gAmazon Full facts →
  3. Optimum Nutrition Gold Standard 100% Whey

    #3Best isolate-led blend

    Optimum Nutrition Gold Standard 100% Whey

    Not a pure isolate, but whey protein isolate is the primary ingredient. 24 g of protein per scoop and a huge range of flavors.

    Protein 24 gBCAAs 5.5 gAmazon Full facts →
Amazon's live top 100 in Protein

What to look for

Isolate first on the label
Ingredients are listed by amount. If whey protein isolate is first, or the only protein, you're getting mostly isolate; blends add concentrate, which is cheaper but has a little more fat, carbs and lactose.
Protein per scoop
Compare grams of protein with the scoop weight. A high protein-to-scoop ratio is a quick sign of a cleaner isolate with less filler.
Third-party testing
Look for NSF Certified for Sport, Informed Choice or Informed Sport if you're a tested athlete or want independent screening. Certifications can vary by flavor and size, so check the label.
Sweeteners
Most flavored isolates use sucralose or other non-nutritive sweeteners. If you avoid them, look for an unflavored version.
Lactose sensitivity
Isolate contains very little lactose, which suits many people with mild lactose intolerance. It still comes from milk, so it isn't suitable if you have a milk allergy.

Frequently asked questions

Is protein powder better with milk or water?

Water gives you just the protein with the fewest calories and a thinner shake; milk adds calories, extra protein and a creamier texture. If you chose an isolate to cut lactose or calories, water makes more sense. Both work for building muscle.

How much protein powder per day?

Most people use one to two scoops a day to fill gaps in their diet, not to replace meals. Total daily protein is what matters; many active adults aim for roughly 1.2–2 g per kg of body weight from food and shakes combined. A dietitian can help you find your number.

Can you take protein powder and creatine at the same time?

Yes. Mixing unflavored creatine into a protein shake is common and convenient, and there's no known interaction between the two.

Is protein powder bad for your kidneys?

In healthy people, research hasn't shown that higher protein intakes from food or powder harm the kidneys. People with kidney disease are often advised to limit protein, so if you have a kidney condition, talk to your doctor before using protein powder.

Sources