Your Quick Guide to Whey Protein

What is Whey?

Whey is one of the two types of protein in milk – you’ll recognize it as the liquid in cottage cheese (remember Little Miss Muffet eating her curds and whey?). Whey is a high quality, complete protein, with all the essential amino acids your body needs. It’s also easy to digest and has a neutral taste—making the whey protein powder an easy addition to foods other than smoothies

Why is Whey Good for Workouts?

  • Whey is an excellent source of branched-chain amino acids (BCAA)1 like leucine, which is known to stimulate muscle synthesis2  
  • Leucine decreases muscle soreness, leading to a shorter recovery time.
  • Whey protein plus resistance exercise can help build more lean muscle than resistance training alone (or combined with carbohydrate consumption).3-5
  • Whey protein after a workout helps build and repair muscle.3,6

How Does Whey Stack up against Soy?

  • Trying to choose a protein powder for your smoothies? Whey vs. soy studies have shown that:
  • People who took whey supplements built significantly more lean muscle mass than those who took soy.
  • Those who took whey had smaller waists than those who took soy.

Lactose Intolerant?

Don’t worry! You can still reap the benefits of whey protein. If you’re lactose intolerant you should opt for whey isolate over whey concentrate, as it contains very little lactose. You can also find whey naturally in low-lactose dairy foods like aged cheeses, lactose free milk, and Greek yogurt.



1. USDA National Nutrient Database for Standard Reference, Release 23.

2. Layman DK, et al. J Nutr. 2003; 133: 261S-7S.

3. Tang JE, et al. Minimal whey protein with carbohydrate stimulates muscle protein synthesis following resistance exercise in trained young men. Appl Physiol Nutr Metab. 2007; 32: 1132-38.

4. Burke DG, et al. The effect of whey protein supplementation with and without creatine monohydrate combined with resistance training on lean tissue mass and muscle strength. Int J Sport Nutr Exerc Metab. 2001; 11(3): 349-64.

5. Phillips SM, et al. Dietary protein to support anabolism with resistance exercise in young men. J Am Coll Nutr. 2005; 24(2): 134S-39S.

6. Howarth KR, et al. Coingestion of protein with carbohydrate during recovery from endurance exercise stimulates skeletal muscle protein synthesis in humans. J Apply Physiol. 2009; 106: 1394-1402. 

By Sarah Ryan, MS, RDN, LD

Sarah is a registered dietitian nutritionist and foodie. She has a special interest in sports nutrition and is certified in food allergy training. When she isn't working, you can find her in the kitchen baking delicious cakes and beautiful pies. Learn more about Sarah

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