Whey is a milk protein. Manufacturers separate whey from milk, then dry and process it into protein powder.

Whey protein is commonly used by athletes, people who regularly exercise and lift weights, and people who want to increase their protein intake.

The most common whey protein supplements are concentrate, isolate, and hydrolysate, each with different nutritional content:

• Protein: Whey protein powders contain 35–95% protein, depending on the product. Hydrolysate has the highest protein content, followed by isolate and concentrate.
• Fat: An 80% whey protein concentrate has about 4–8% fat. Whey isolate and hydrolysate have very little fat.
• Lactose: Whey protein concentrate has 4–10% lactose, which can upset digestion in people with lactose intolerance. Whey isolate and hydrolysate have less lactose.
• Minerals: Each type contains minerals like calcium, magnesium, zinc, potassium, and sodium. Whey concentrate generally has higher mineral content than isolate and hydrolysate.

Pros of Whey Protein

Whey protein has some advantages:

• Provides high protein content with all essential amino acids.
• Rich in leucine, an amino acid that strongly supports muscle growth.
• Easily digestible, meaning your body breaks it down and absorbs it efficiently.
• Has a creamy taste that most people find pleasant.
• Suitable for people with soy or nut allergies. However, always check the package for nut-free or soy-free labeling, as there may be potential cross-contamination in manufacturing facilities.
• Gluten-free, making it suitable for people with gluten intolerance or celiac disease. Check the package to confirm the product has gluten-free labeling.
• Often lower in carbs than plant protein concentrates. This makes it a better option for people on a low-carb diet. Always check the nutrition facts label for carb content.

Cons of Whey Protein 

Whey protein has some disadvantages:

• Contains lactose, which can upset digestion in people with lactose intolerance.
• Is derived from milk, meaning people with milk allergies can’t take whey protein.

Plant-based protein comes from sources like soy, pea, rice, hemp, peanuts, or pumpkin seed. Manufacturers remove starch and fiber using enzymes and then dry the protein into a powder.

Many people use plant proteins to support muscle growth and boost daily protein intake, particularly those following vegan or vegetarian diets.

The most common plant protein supplements are concentrate and isolate. Plant protein hydrolysates are not as common, but they are available. The nutrient content of plant-based proteins differs depending on the brand and type:

• Protein: Plant protein content ranges from about 50% to over 90%. Isolate or hydrolysate varieties generally have higher protein than concentrate:
• Soy concentrate: 50–71%
• Soy isolate: 92–95%
• Pea concentrate: 51–55%
• Pea isolate: 82–88%
• Fava bean concentrate: 55–67%
• Fava bean isolate: 91–93%
• Rice isolate: 83–92%
• Carbohydrates: Concentrates usually have more carbs than isolates or hydrolysates. For example, soy protein concentrate with 64% protein contains 25% carbs, while soy isolate with 88% protein has almost no carbs.
• Lactose: Plant proteins are naturally lactose-free. Check the label if you’re very sensitive to lactose, as some may contain trace amounts from cross-contamination.
• Fat: It generally ranges from 0.1% to 10%. Fat content may be higher in plant protein powders made from seeds or other plants naturally high in fat.
• Vitamins and minerals: Plant proteins can provide nutrients like calcium, iron, magnesium, phosphorus, potassium, zinc, and folate, depending on the plant source. Isolates and hydrolysates usually contain lower amounts of these vitamins and minerals.

Pros of Plant Protein

Plant protein has some advantages:

• Does not contain lactose. This makes it ideal for people with lactose intolerance.
• Suitable for people with milk allergies or those following a dairy-free diet.
• Does not come from animal sources. It’s suitable for people following vegan, vegetarian, or other plant-based diets.

Cons of Plant Protein 

Plant protein has some disadvantages:

• Often higher in carbs than whey protein, which may be less suitable for people following strict low-carb diets.
• May lack certain essential amino acids, depending on the product. However, many plant protein powders combine different sources to provide all essential amino acids, including leucine.
• Has lower digestibility than whey protein. Whey ranges from 98–100% digestible, soy from 95–98%, and pea from 83–90%.
• Soy, peanut, and other nut-based protein powders are not suitable for people with soy, peanut, or nut allergies.

Key factors to consider when choosing a protein supplement include:

• Your dietary needs: Choose a protein powder that fits your diet and any allergies or intolerances. Many options are available, including dairy-free, lactose-free, gluten-free, keto-friendly, paleo-friendly, organic, non-GMO, or fortified with vitamins and minerals.
• Your goals: The product best for you will depend on whether your primary goal is to build and maintain muscle, manage weight, meet daily protein needs, or improve recovery after workouts. For example, if your goal is muscle growth, select a supplement with high protein content that includes all essential amino acids, especially leucine.
• Budget: Consider serving size and price to determine the most cost-efficient option.
• Look at ingredients: Both plant and whey supplements may contain additional ingredients to boost performance and recovery. Read the ingredients to ensure the product doesn’t contain anything you don’t want.
• Check third-party testing: The U.S. Food and Drug Administration (FDA) doesn’t regulate dietary supplements before they are on the market. Some products are tested by third-party labs to ensure their safety and accurate labeling. You can look for supplements with certifications such as NSF Certified for Sport or Informed-Sport.

Plant protein supplements are usually a better option for:

• People with milk allergies
• People following vegan, vegetarian, or other plant-based diets
• People looking for more sustainable options
• People who want to mix their sources of protein

Whey protein supplements are usually a better option for:

• People looking for higher protein absorption with less product
• People with soy, nut, or peanut allergies
• People with gluten intolerance or celiac disease

Both whey and plant proteins help build and maintain muscle. Whey provides all amino acids and is easy to digest. Plant protein is a good option if you want lactose-free, vegan, or more sustainable supplements.