You just finished a sweaty and heavy training session at the gym. As you revel in your hard work, one of the most enjoyable moments of that post-workout high can be downing a delicious shake packed with the nutrition you need to get your gains. Whey protein is one of the most popular supplements that you may find yourself popping into your drink.
Whey protein is a quality and complete protein source that you’ll want on your team to support goals from building muscle and increasing strength to losing body fat. Strength athletes of all genders and ages will want to get in on the muscle-building amino acid leucine and health-booster cysteine.
From strength and muscle gains to longevity and holistic health, here’s the behind-the-scenes science of the benefits of whey protein — and who should be adding it to their shaker bottles.
Editor’s Note: The content on BarBend is meant to be informative in nature, but it should not be taken as medical advice. When starting a new training regimen and/or diet, it is always a good idea to consult with a trusted medical professional. We are not a medical resource. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. They are not substitutes for consulting a qualified medical professional.
What Is Whey Protein?
Protein is one of the macronutrients — alongside carbs and fats — that supports your overall health. It’s the key to building muscle and crushing strength goals.
Whey refers to a component of milk that emerges during the manufacturing of cheese. Refining whey by removing water and some lactose leaves mostly protein behind. That process yields different types of whey protein powder. (1)
As a complete protein source, whey contains all nine of your essential amino acids — including the popular branched-chain amino acids (BCAAs) favored by many strength athletes. Your body can’t produce essential amino acids on their own, so you need to ingest them to get their support building muscle and enabling other key functions. (1)(2)
Whey is high in leucine, which is the BCAA most important for muscle-building because it is a precursor for muscle protein synthesis. (3) Whey protein is also high in cysteine — a non-essential amino acid that’s been shown to function as an antioxidant in your body. It may raise your levels of glutathione, which can help to fight inflammation and diseases. (1)
In addition to being a complete protein, you may have also heard that whey is a high-quality protein source. This means that its amino acids are readily available and can be quickly absorbed and digested. (1) Therefore, whey protein can deliver those amino acids to your skeletal muscles right away to help them grow after resistance training.
Sources of Whey Protein
Whey protein is found in animal-based food sources and in supplement form. While whey protein supplements can be highly beneficial to strength athletes, they are processed and stripped of other nutritional qualities. So, protein powder is not a complete source of other nutrients that you’ll find in natural food sources.
Health professionals often recommend that you try to reach your protein intake goals through food and consider supplements an addition to a healthy diet. (4)
[Read More: The Definitive Guide to Bodybuilding Meal Prep]
Below are some natural food sources of whey protein.
- Dairy Products
Types of Whey Protein Supplements
There are three main types of whey protein powder that lifters reach for and they differ in the way they are processed.
Whey protein concentrate is one of the most popular and affordable supplements. Water and some lactose have been removed. Due to its minimal processing, it may contain most of the biologically beneficial components of whey. (1)
Whey protein isolate is further processed to remove most of its lactose, fat, and carbohydrates. It may be better tolerated for folks who are lactose intolerant. It has the highest amount of protein, but it may lose some of its other benefits through processing. (1)
Whey protein hydrolysate differs in that it has been pre-digested and already broken down into amino acids. It can be absorbed even more quickly than the previous types. (1) It tends to be more expensive. This is another good choice for folks who are lactose intolerant or have other digestive issues.
Potential Benefits of Whey Protein
Whey protein contains all nine essential amino acids needed to build muscle and support your overall health. It’s quickly absorbed and can be transported right to your skeletal muscles. These properties may provide several benefits to strength athletes and anyone looking to support their health through adequate protein intake. Let’s dive in.
May Help Build Muscle
Research has consistently shown that when combined with resistance training, whey protein can increase muscle protein synthesis in people of all ages and genders. (5)
Protein intake is necessary for building muscle, but you can reach your goals through natural food sources alone. When it comes to supplements, research shows that the quality of your protein can have a greater effect — and whey protein is considered one of the highest-quality sources. (6)
Whey is considered complete and high-quality because it contains all of your essential amino acids, which include BCAAs and leucine. (6) All of these components are then able to be quickly digested and absorbed, leading to gains after you’ve broken down your muscles in the gym.Research has found that a serving of 20 to 25 grams of whey protein after resistance training can help to optimize muscle protein synthesis. (7) Studies also suggest that whey might have the ability to stimulate greater muscle protein synthesis than supplements containing casein and soy. (6)
May Improve Recovery
Consuming whey protein as part of hitting your daily protein intake goals may help improve exercise recovery. Protein has long been established as a vital component of muscle recovery because it helps to repair tissue and cell damage while stimulating hormonal and metabolic activity. (8) Since whey protein is quickly absorbed, it can get to work in your body right away repairing and rebuilding damaged muscles after a workout.
When you work out, your body uses glycogen for energy. After training, you need to replenish your glycogen stores. Research has shown that consuming whey protein isolate along with carbohydrates can help refill your muscle glycogen stores, which can lead to better recovery. (9)
[Read More: The Complete Guide to Pre-Workout Supplements]
Whey protein also has anti-inflammatory and antioxidant abilities that may help to combat oxidative stress caused by exercise. Whey contains the amino acid cysteine, which can be converted to glutathione — a powerful antioxidant that fights cellular damage. (10)
Some inflammation after exercise is a good thing, as it leads to repair and growth. However, inflammation can also cause pain and reduce skeletal muscle function. (11) In theory, less inflammation may reduce symptoms of delayed onset muscle soreness (DOMS), but more research is needed.
May Increase Strength Over Time
Due to its muscle-building and recovery-enhancing abilities, whey protein may help improve your athletic performance over time. Whey protein is not a pre-workout supplement and won’t have any immediate effects in a one-off training session.
But consistently showing up to the gym to crush your workouts with optimally-recovered muscles can help you lift heavier throughout a training program. So while it might not directly bolster a new personal record, whey protein can help you get the consistency and muscle size you need to perform at your highest level and increase strength in the long run.
Some populations may benefit from short-term strength gains with whey protein, though. In one study conducted with a group of older women, researchers found that whey protein supplementation yielded gains in both muscle mass and strength. (12)
May Support Fat Loss
When following a dietary and training program for fat loss, whey protein can majorly support your efforts. Protein is known to be the most satiating of the macronutrients. If you are in a caloric deficit or otherwise reducing your intake, protein can help you feel fuller for longer, which can help you stick to your plan.
Diets high in protein may also have a greater thermogenic effect on your body than other macronutrients. (13) Protein has a higher thermic effect of food (TEF), which means it requires more energy to digest. (14)
After consuming whey protein, your body needs to expend more energy and your metabolism temporarily increases. Theoretically, this can marginally increase your total daily energy expenditure (TDEE), which supports fat loss.
Whey protein also supports fat loss by helping you maintain your lean muscle mass as you lose body fat. (13) While you can theoretically lose weight by simply eating fewer calories than your body needs, including whey protein in your diet, can help you hang onto your lean muscle mass. (15)
May Improve Bone Health
Whey protein — in conjunction with vitamin D and calcium — may help improve and protect bone health in aging adults. Natural muscle loss or sarcopenia can occur as humans get older. Bone mineral density and bone strength can also naturally decline. These conditions, osteopenia and osteoporosis, are more common in women and people assigned female at birth. (16)
Weight-bearing resistance exercise and adequate intake of vitamin D and calcium are often recommended as ways to prevent these conditions. Research suggests that whey protein may help increase calcium absorption. (17)
For example, one study focused on a group of older adults with sarcopenia. They consumed a supplement containing vitamin D, calcium, and leucine-enriched whey protein for 13 weeks. The study concluded that the supplement had a small but significant effect on improving their bone mineral density and increasing their bone health. (16)
Whey protein may contribute to bone health — but is only one piece of the longevity puzzle.
May Lower Blood Pressure
If you have hypertension, some studies have shown that consuming whey protein may help to lower your blood pressure and support cardiac health. (18) This may be because there are peptides from milk proteins that can function to lower blood pressure. (19) The peptides in whey protein are called lactokinins and contribute to this effect, but more research is needed. (20)
Another possibility is that whey protein stimulates nitric oxide production in your body. Since whey protein contains all essential amino acids, it includes L-arginine, a precursor to nitric oxide. Nitric oxide widens your blood vessels, increases blood flow, and has been shown to lower blood pressure. (21)
Whey Protein Myths
Some misinformation surrounds the popular protein supplement. Let’s debunk a few of them.
Myth: All whey protein supplements are the same.
Whey protein supplements come in three different types:
- Whey concentrate is the most popular — it comes in many flavors and is minimally processed so it retains most of its lactose and fat.
- Whey isolate has less lactose and fat in it and packs even more protein than whey concentrate.
- Whey hydrolysate is pre-digested and can be on the pricier end.
Myth: Whey protein will make me lose weight.
Whey protein alone will not cause weight loss, but it can be a great addition to a fat-loss plan. Instead, this supplement can help increase your satiety and preserve muscle mass when losing body fat.
Even if you are new to training, you already have lean muscle mass — if you are trying to lose fat, it is beneficial to maintain the muscle. Including whey protein in your diet combined with resistance training can have a greater impact on your fat loss journey than simply reducing caloric intake.
Myth: Women should not take whey protein.
Whey protein can be beneficial for all genders. Whey protein will not make women “bulky.” Protein powder is not just for men — everyone needs protein in their body and whey protein is simply an efficient way to boost your intake.
Potential Drawbacks of Whey Protein
Just as there are potential benefits to whey protein, there are also potential drawbacks. Here are a few things to consider when deciding whether or not it’s right for you.
May Cause Digestive Issues
Whey protein can cause bloating, gas, and stomach discomfort. If you are sensitive to lactose or are lactose intolerant, this may be the culprit. Choosing a different form of whey may help.
Whey protein isolate has less lactose than whey concentrate but is not completely lactose-free. Whey hydrolysate has even less lactose than isolate. But if you are lactose intolerant, all of these products may cause issues for you.
Not for Vegans
Since whey comes from cow’s milk, whey protein is not a vegan-friendly product. Food sources containing whey are all animal-based. Check out some of the best vegan protein powders and how to build muscle on a vegan diet.
Can Be Pricey
High-quality whey protein can be expensive. If you’re able to hit your protein intake goals through whole foods, choosing animal-based protein sources can help you get the benefits of whey without the extra cost.
One More Scoop
There’s a reason that strength athletes reach for whey protein when they’re filling their shaker bottles.
Whey protein is a complete and high-quality animal-based protein source. It contains all essential amino acids and is quickly absorbed so it can get straight to work delivering nutrients to your muscles. It’s been heavily researched and shown to help build skeletal muscle after resistance training. It also may help with other overall health issues, ranging from blood pressure to bone density.
Hit your protein goals through your daily intake of nutrient-dense natural food. If you need a little help getting to the protein levels you want, toss a scoop or two of whey protein into your next shake to make the most out of your strength training.
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