Whey Protein – Benefits for Muscle Health

Whey Protein – Benefits for Muscle Health

Written by: Ryah Nabielski, MS, RDN

Whey protein is the most popular and studied protein supplement. The benefits of whey protein for muscle growth, strength, and recovery are well established, making it an excellent choice for athletes, women, older adults, and anyone who wants to improve or maintain muscle mass. 

Today’s article will take a closer look at whey protein and the research on using it to improve body composition. We will cover:

  • Whey protein basics
  • Amino acid composition of whey protein 
  • How whey protein supports muscle health 
  • Additional health benefits
  • Side effects and safety 
  • Why quality matters
  • How to incorporate whey protein into your routine

Let’s get started! 

What is Whey Protein?
“Little Miss Muffet sat on a tuffet, eating her curds and whey….”

When you add enzymes to milk to make cheese, the milk separates into curds and whey. The curds are the solid part containing most of the milk fat and casein protein. The liquid whey contains whey protein and lactose (milk sugar). Drying the liquid whey produces whey protein, which is then processed and added into protein powder formulas.  

Whey Protein Composition 
Many of whey protein’s health and muscle-building attributes have to do with its amino acid composition. Amino acids are the individual building blocks of protein, and each one serves different actions in the body, with some being more critical for muscle health. Across various protein-containing foods and protein powders, you’ll find considerable variations in amino acid composition. 

Whey protein is a highly effective protein powder for strength and performance because it is a complete protein, contains branched-chain amino acids, and is high in leucine. 

Whey protein is a complete protein.
Whey is “complete” because it contains all nine essential amino acids. While the body can make some amino acids from others, the essential amino acids must be obtained from the diet to support body structure and function. 

After eating, increases in essential amino acid concentrations drive protein synthesis (protein building) throughout the body, including in the muscles. 

Whey protein contains branched-chain amino acids. 
The three branched-chain amino acids (BCAAs), leucine, valine, and isoleucine, comprise about one-third of all muscle protein. Needless to say, building and maintaining muscles requires a good amount of BCAAs, which you’ll find in whey. 

In addition, when you consume BCAAs with optimal overall daily protein and essential amino acids, you’ll have the perfect conditions for protein synthesis. 

Whey protein is high in leucine. 
Leucine is one of the branched-chain amino acids and the most researched for its anabolic (muscle-building) effects. Whey protein is a significant source of leucine, much higher than most plant proteins, which helps explain why it’s so effective at stimulating muscle synthesis. 

Exercise leads to a decrease in leucine levels in the body. Consuming leucine around exercise may prevent protein breakdown, promote fat loss, and improve performance. 

Whey Protein and Muscle Health 
One of the primary benefits of supplementing with whey protein is its effect on skeletal muscles. It supports lean muscle growth, muscle maintenance, and muscle recovery. 

Lean muscle growth 
Combining strength training and whey protein supplementation leads to muscle growth and improved muscle strength. Whey has benefits across populations, in both young and old. 

The strain from strength training causes muscles to break down, which promotes the rebuilding of the muscles afterward. This process, over time, creates gains in muscle mass and strength. Studies suggest whey protein accelerates the process of muscle regeneration after exercise. 

Total protein intake is essential, and whey protein is also unique. It stimulates muscle protein synthesis more than other protein sources, including casein and soy. 

Muscle maintenance 
Muscle mass declines with age. Slowing or preventing muscle loss has many benefits for health and longevity. Maintaining muscle mass is essential in older adults, those with an illness or chronic disease, and those actively losing weight. 

Older people are at risk of sarcopenia, a muscle-wasting condition associated with aging or immobility, where muscle mass and strength decline. Sarcopenia increases the risk of falls and reduces life quality. Supplemental whey protein may help attenuate muscle loss associated with aging and disease. 

Whey protein may also help preserve lean body mass during weight loss when you are at risk of losing muscle along with fat. Using whey protein as part of a weight-loss strategy promotes protein synthesis.  

Muscle recovery
Muscle recovery refers to the repair phase after exercise when you may feel fatigued, soreness, stiffness, and inflammation. In addition to improving and maintaining muscle mass, whey protein may enhance muscle recovery after exercise. Improving recovery time and effectiveness can boost your training strategy and performance. 

Learn more about how to optimize your muscle recovery in this article

Additional Whey Protein Benefits
Muscle health is at the top of the list for whey protein benefits. However, it’s important to point out that muscle mass is crucial for more than strength and physical appearance. Increasing or maintaining lean body mass improves metabolic health, improves physical function, and helps prevent chronic disease, all of which become more important with age. 

Another benefit of whey protein supplementation is its effect on antioxidant status. Exercise, toxin exposures, and daily living all produce oxidative stress in the body. Antioxidants work to counter that stress. Because whey protein is high in the amino acid cysteine, it promotes the production of glutathione, the body’s “master antioxidant.” One study showed that supplementing with 45 grams of whey protein for two weeks increased glutathione levels by 24%! 

Side Effects and Safety
Whey protein comes from dairy and should not be consumed by those with a dairy allergy. For those with lactose intolerance or dairy sensitivity, individual tolerance of whey protein may vary. Please discuss concerns with your healthcare provider or dietitian. If whey isn’t a good fit for you, consider collagen-egg protein or vegan protein instead. 

Whey protein is an excellent choice for those who tolerate dairy, but quality matters. 

Whey Protein Quality 
Not all whey protein products are created equal. It’s important to consider the source, type of whey protein, and other ingredients in a formula. 

The quality of whey protein is only as good as the quality of the milk it begins with. Twenty2 Nutrition uses whey from grass-fed cows that live on pasture for their entire life. Learn more about the new whey protein source Truly Grass Fed here

Twenty2 Nutrition Grass Fed Whey Protein contains whey protein isolate, which is lower in fat and lactose and contains 90% protein compared whey protein concentrate. In addition, low lactose and added digestive enzymes in Twenty2 Nutrition Grass Fed Whey may improve tolerance and digestibility.

Whey Best Practices for Use
Whey protein works best with a diet that meets your daily protein needs. Studies show that consuming a minimum of 20 grams of protein helps stimulate muscle growth and maintenance following a meal or snack. In addition to dietary protein, incorporate whey protein as a supplement for all the benefits outlined here. 

Twenty2 Nutrition Grass Fed Whey Protein contains 25 grams of whey protein per scoop and comes in three flavors – Chocolate, Cookies & Cream, and the new flavor option coming soon! It mixes well into milk or a shake with a smooth, non-chalky texture. Try it in the morning as part of breakfast, before exercise to fuel your workout, or after strength training to promote muscle growth and recovery.

Regarding muscle health, whey protein has the most positive data supporting its use. It isn’t just for bodybuilders; everyone benefits from improving and maintaining lean body mass now and throughout life. 

This article is for educational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified healthcare provider before beginning a new supplement, especially if you are pregnant or breastfeeding, take medication, or have a medical condition. 

Ryah Nabielski, MS, RDN is a Registered Dietitian, functional nutritionist, writer, and recipe creator. Ryah helps clients use a natural, food-as-medicine approach to improve fertility, pregnancy, hormone balance, autoimmunity, and discover a healthy relationship with food and body. Learn more about Ryah and her private practice at econutrition.co


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