Most people think of whey protein as a strength supplement. Something to build muscle after a hard workout. That about covers it, right?
Not even close. Whey protein does enhance muscle growth and recovery, but — thanks to the special properties of this milk-derived peptide — it enhances so much more than just muscle. And the benefits of whey protein can help men and women of all ages, sizes, and activity levels.
Whey supplementation, in fact, has been shown to improve body composition, prevent age-related muscle decline, boost immunity, and decrease disease risk. Don’t worry, there’s plenty of research to support these claims.
With that in mind, here’s what you’ll learn today:
- Getting To Know Whey
- Benefit 1: Improved Body Composition
- Benefit 2: Weight Loss On Keto
- Benefit 3: Better Metabolism
- Benefit 4: Muscle Growth And Recovery
- Benefit 5: Preventing Age-Related Muscle Loss
- Benefit 6: Immunity
- Benefit 7: Antioxidant Support
- Benefit 8: Liver Health
- Benefit 9: Anticancer Effects
- Benefit 10: Heart Health
- Benefit 11: Cognitive Health
- Benefit 12: Gut Health
- Whey Benefits Reloaded
- How To Take Protein Supplements
- People Of Different Activity Levels
- Staying Strong As You Age
- Pregnant Women
- General Protein Safety
- Choosing A Protein Powder
Okay. Basics first, then benefits. Buckle in.
Most whey protein, you’re probably aware, comes from cow’s milk (although you can find some from goat’s milk). And milk contains two primary proteins: casein (about 80%) and whey (about 20%).
When you separate dairy solids from the liquid, you get whey (the liquid) and casein (the solid). When the liquid is spray dried into a powder and filtered, you get either whey concentrate or whey protein isolate.
Isn’t as filtered and still contains some lactose (a fermentable sugar that can cause digestive upset for some people), plus other compounds. This one also doesn’t contain as much protein as the isolate.
Whey Protein Isolate
Whey protein isolate (WPI) is the purest form of whey, with over 90% protein by volume and very little lactose[*]. Because it’s low in the milk sugar lactose, whey isolate is a good choice for people with lactose intolerance. Yes, over 10% of the population have trouble digesting milk sugar.
Whey isolate — or any form of whey, for that matter — is not appropriate for those with a dairy allergy. That’s because whey contains alpha-lactalbumin and beta-lactoglobulin — normally beneficial compounds that also happen to be milk allergens[*]. This isn’t, as you might imagine, a side effect to mess around with.
A few more things. Whey isolate can be hydrolyzed, or split apart, to create whey protein hydrolysate. This form may be better absorbed[*].
Also, pay attention to the origins of your whey protein. If your whey comes from grass-fed cows, it not only has more bioactive compounds like lactoferrin and beta-lactoglobulin — it’s also better for the environment[*].
Ranchers that raise grass-fed cows tend to use rotational grazing methods that spare the soil. Organic farmers also use fewer antibiotics for their livestock — and this helps lessen the growing threat of antibiotic-resistant superbugs[*].
Okay, you’ve gotten to know whey a bit. Now it’s time to meet the benefits.
Whey protein, you’ve probably heard, helps build muscle. But maybe you don’t want bulky muscles. You’d have to buy new clothes to fit around your biceps.
Instead, maybe you’re trying to slim down and stay lean in the process. You haven’t considered whey — a “muscle growth supplement” — as a “stay lean supplement” too.
That’s about to change. Whey preserves lean muscle mass and increases fat loss during periods of weight loss. In other words, whey helps improve body composition.
Researchers at Purdue recently compiled thirteen studies on whey supplementation for women. Body mass index (BMI) was the primary endpoint[*].
When the data was calculated, they found that whey protein improved body composition across the board. This means that when women supplemented with whey, they had more lean mass than the control groups. This effect was most significant in studies with a calorie-restriction component.
So no, whey doesn’t always bulk you up.
In another study, researchers put 34 women recovering from gastric bypass surgery on two diets — low calorie with whey, and low calorie without whey. All 34 women lost weight, but the group that supplemented with whey maintained their muscle mass[*].
Simply put: whey doesn’t stimulate weight loss per se, but it can help you feel full so you eat fewer calories overall; and it will help you maintain muscle even as you shed fat.
And when it comes to losing weight, it’s hard not to mention the ketogenic diet.
You probably know that a high fat, low carb ketogenic diet stimulates weight loss[*]. But in case you forget why this happens, here are three reasons:
- Keto Burns Fat: When you follow a keto diet, your body goes from burning glucose to burning fat for energy. Yes, you’ll burn dietary fat, but you’ll also burned stored fat — or adipose tissue — over time.
- Keto Decreases Appetite: On keto, you naturally eat less. Keto lowers your appetite by[*]:
- Decreasing your hunger hormone, ghrelin
- Decreasing a hunger chemical in the brain called neuropeptide Y
- Increasing a stomach peptide called CCK, which suppresses hunger
- Keto Lowers Insulin — when you eat fewer carbs, you avoid high blood sugar. This helps prevent insulin resistance — a condition in which too much insulin gets your body storing instead of burning fat. Avoiding carbs helps lower insulin — your fat-storage hormone.
Adequate protein intake is essential for maintaining lean mass on a ketogenic weight loss program. And no, eating protein will not stop you from losing weight on keto.
This 2016 study, for example, was another low-calorie weight loss trial with whey protein. Researchers put 25 healthy people on two diets: a low-calorie diet, and a keto diet with whey supplementation. Again, body composition was the endpoint[*].
By the end, the keto with whey group had better body composition than the low calorie group. Although both groups lost weight, only the keto folks kept their lean mass. Which means that whey protein should probably be in your keto cupboard.
Whey is an excellent supplement to add to your weight loss stack. And whey has metabolic benefits, too. Let’s find out what that means.
What you eat affects your metabolism. Take a high-carb diet — a notorious promoter of metabolic disorders.
When you’re healthy, here’s what happens when you eat a high-carb meal:
- You eat a high carb meal
- Your blood glucose rises
- Your pancreas releases insulin to move that glucose into your cells
- Your blood sugar drops again to healthy levels
But if you keep eating high carb meals, that process can morph into this:
- You eat high carb meal after high carb meal
- Your blood glucose spikes after each meal
- Your pancreas releases gobs of insulin to handle the blood sugar spikes
- Eventually your cells become insulin resistant (they stop taking up glucose)
- Your blood sugar stays elevated, increasing your risk for chronic disease
- Your insulin also stays elevated, increasing your risk for chronic disease[*]
- All that insulin keeps your body in fat storage mode
- You get stuck in this insulin resistant state
That’s why, if you’re going to talk about obesity, you have to talk about diet, blood glucose, and insulin. They’re all linked.
And when it comes to improving insulin function, and therefore blood sugar regulation, whey protein seems to help.
Whey Helps Balance Blood Sugar
In one trial, researchers gave either whey, casein, or glucose to obese people for 12 weeks. No surprise here that the group that took the whey supplement had better insulin function[*].
Another trial involved giving whey protein to type 2 diabetics along with a high-carb breakfast. The results were encouraging. Following breakfast, type 2 diabetics given whey had improved insulin sensitivity and lower blood sugar than the placebo group[*].
To be clear: these studies were on populations with existing metabolic disorders. It’s not clear if whey has these benefits in healthy populations.
What is clear, however, is that whey can promote muscle growth and recovery in most anyone.
Whey protein is great for muscle protein synthesis — and this benefit is largely due to its amino acid composition. Amino acids are the building blocks of protein molecules. You need them to form every tissue in your body.
Amino acids, by the way, are categorized as essential and non-essential. Essential aminos must come through diet, while non-essential aminos are technically synthesized in your body.
A protein with all nine essential amino acids — like whey protein — is called a complete protein.
But when it comes to muscle growth and repair, branched chain amino acids or BCAAs are doing a lot of the heavy lifting.
Whey just happens to be rich with BCAAs, aka leucine, isoleucine, and valine. Because of this, whey is ideal for exercise recovery.
People fed a whey supplement — versus a soy or carbohydrate supplement — had significantly more lean mass than those fed carb or soy[*]. Probably because whey has higher levels of the BCAA leucine.
Another group of researchers examined the short-term recovery effects of whey. They gave 12 young men either a whey protein supplement or a carb supplement before a weight lifting session, then measured muscle strength and recovery at 12 and 24 hours post workout. The whey supplemented group recovered better, faster, and stronger than the control group[*].
But whey’s BCAAs are not just for the gym. They’re also useful for preventing age-related muscle loss.
There’s a common misconception that, as you age, your body has to deteriorate. Many people do lose muscle as they age, for instance. But you don’t have to.
Muscle loss, or sarcopenia, causes problems like weakness, nerve damage, and increases your risk of chronic disease[*]. And it’s avoidable.
To prevent sarcopenia, you’ll want (at the very least) to do these two things:
- Lift weights
- Eat enough protein — preferably protein high in BCAAs, like whey
Both protein and resistance training are crucial for maintaining lean mass into your later decades. If you lift three times a week, but don’t eat enough protein, your muscles will pay the price.
Along these lines, researchers gave 70 older women either whey or placebo (before and after weight training) for 12 weeks[*]. At the end of this randomized controlled trial, the women on whey had more lean mass — and more functional strength — than the control group. So if older adults want to prevent muscle loss, taking whey before or after a workout can help.
Now you know the details behind whey’s muscle-building benefits. And now it’s time to shift gears to whey’s less well known health benefits.
If whey protein only contained amino acids, it would still be a marketable supplement. Whey is a complete protein high in muscle-building BCAAs.
But whey is deeper than that. Not emotionally. Physically.
In addition to its essential amino acids, whey is brimming with bioactive, immune-boosting compounds. Here’s a few:
- Beta-lactoglobulin: Comprising around 50% of whey protein, this peptide appears to enhance the human immune response. For instance, beta-lactoglobulin has antimicrobial and anticancer properties — and is helpful for patients with severe sepsis infections[*]. Whey from organic farms has more B-lactoglobulin than whey from conventional farms[*].
- Alpha-lactalbumin: This protein makes up about 36% of whey. A component of breast milk, alpha-lactalbumin is crucial for the gut development and immunity of the growing fetus[*].
- Lactoferrin: Another milk protein with immune-boosting and anticancer activity[*].
- Immunoglobulins (IGG, IGA) — IGG and IGA are immune particles that fight infection. These immunoglobulins bind to antigens (bacteria, virus, etc.) and help signal your immune system to destroy them[*].
- Lysozyme and lactoperoxidase — Potent antibacterial enzymes found in whey protein[*].
These compounds do more than influence immunity — and some of them will resurface in later sections. But first you need to learn about another amino acid: cysteine.
Cysteine is technically a non-essential amino acid, which means you can synthesize it on your own. But that doesn’t mean you can’t use more of it.
Why? Because cysteine boosts your internal antioxidant response.
You need this response. Every second of every day, your cells generate particles called reactive oxygen species (ROS). These particles include hydrogen peroxide, nitrous oxide, superoxide, hydroxyl, and a long list of others. ROS are just part of living.
In fact, at low levels: ROS are actually beneficial — acting as signaling molecules for your immune system and cellular defense mechanisms. At high levels, however, ROS create oxidative damage throughout your body. Eventually, your body will succumb to this damage and you’ll likely form conditions like autoimmunity, neurodegenerative disease, heart disease, and accelerated aging[*].
Here’s the good news. To keep ROS in check during times of stress or illness, your body has a protector. That protector is called glutathione.
Glutathione is known, for good reason, as your master antioxidant. When oxidative stress rises, your body ramps up glutathione production to clean up those pesky ROS.
And you need cysteine to make glutathione.
Now it’s all making sense. Whey is high in cysteine, cysteine supports glutathione production, and glutathione mitigates oxidative damage.
To see how this affects chronic disease, look no farther than the liver.
The liver doesn’t get a lot of love, but it’s just as important as your heart or your brain. Your liver secretes digestive bile to help you break down dietary fat, clears toxins from your blood, regulates your cholesterol levels, regulates your metabolism, produces clotting proteins — the list goes on[*].
Sadly, liver health seems to be on the downswing in the developed world — with non-alcoholic fatty liver disease (NAFLD) now affecting 20-30% of the population[*]. NAFLD involves fat building up on the liver, and it’s bad news for liver function and disease risk.
Enter: whey. High in cysteine, whey may help your body replenish glutathione stores, which can decrease oxidative stress on your liver.
Researchers gave 20 grams whey isolate per day to 38 patients with liver disease for 12 weeks. By the end of the trial, not only had glutathione production improved — but the health of the actual liver cells (hepatocytes) had improved too[*].
In another study, 11 obese women with liver disease were given whey protein supplementation. All of the women experienced a decrease in liver size and triglycerides[*].
In addition to impacting liver health, cysteine-rich whey may also impact cancer.
Cancer is complicated, but researchers have noticed that high levels of ROS often accompany the formation of tumors[*]. This oxidative stress depletes glutathione — your cellular protector — and things get worse from there.
And so, researchers speculate, replenishing glutathione with cysteine-rich whey protein may help combat cancer.
There’s literature in both animals and humans that whey protein may suppress tumor growth[*]. These anticancer effects are due, at least in part, to cysteine. But lactoferrin, another compound in whey, is also part of the picture.
One reason cancer is so devastating? Because cancer switches off apoptosis — or programmed cell death — in human cells. In this way, cancer cells become immortal.
Lactoferrin may help. It’s unclear exactly how it works, but lactoferrin appears to increase cell death in cancer cells[*]. There’s clinical evidence to back this up.
In a 2014 controlled trial, patients with colorectal polyps took either lactoferrin or nothing for a full year. At year’s end, polyp growth was suppressed only in the high-dose lactoferrin group. Good to know[*].
Now on to the heart.
There are many factors influencing heart disease risk: weight, insulin resistance, lipids, endothelial health, inflammation — the list is long. One could spend a lifetime learning the relevant biomarkers.
You’ve already learned about two of them today. Recall, if you will, that whey improved both insulin sensitivity and blood glucose levels in overweight people[*]. In addition to these benefits, a massive 2013 review found that whey supplementation also improved blood pressure, arterial health, and blood lipids in people with metabolic syndrome[*].
In one trial, 42 mildly hypertensive folks got either whey, casein, or sugar supplements for eight weeks. Since this was a crossover study, each person functioned as their own control — meaning that everyone received eight weeks of whey, eight weeks of casein, and eight weeks of sugar[*].
Compared to casein and sugar, whey protein significantly improved blood pressure. Whey also lowered triglycerides — another risk factor for heart disease.
Okay, so whey seems to be good for the heart. But what about the brain?
Your brain contains chemicals called neurotransmitters. Neurotransmitters help determine how you think, feel, and act in every moment of life.
Serotonin — best known for mood regulation — is one such neurotransmitter. Lower levels of serotonin are not only linked to depression, but also linked to impaired cognitive performance. One thing that depletes serotonin, and therefore hinders cognitive health? That would be stress.
With this in mind, researchers guessed that improving serotonin status with a high tryptophan supplement would improve brain function in stressed out people[*]. That high-tryptophan supplement was alpha-lactalbumin — a peptide that, if you recall, accounts for 36% of the protein in whey.
And it worked. Alpha-lactalbumin supplementation boosted tryptophan levels and improved memory in stress-prone people.
In mice, whey significantly lowered oxidative stress and improved mitochondrial function in the brain[*]. These factors, by the way, are linked to age-related cognitive decline and neurodegenerative disease in humans.
In sum: whey may improve cognitive health by lowering oxidative stress and boosting serotonin levels in the brain. That brings us to your gut, where you produce about 95% of your serotonin[*].
Your gut is a long tube beginning at your mouth and ending you know where. When your gut is working properly, you break down food in your stomach, absorb nutrients in your intestines, and release toxins in your stool.
But for one reason or another — inflammation, antibiotics, food allergies, infection, etc. — your intestinal wall (only one cell thick) can become damaged. This is called leaky gut. Here are a few bullets on that:
- Your intestinal wall suffers damage
- Large particles (food or toxins) start to leak through the intestine and into the bloodstream
- Your immune system freaks out and attacks these particles, creating inflammation
- This inflammation damages the gut further, making it leakier
- The cycle continues
Leaky gut (and the associated inflammation) is linked to many chronic diseases, especially gut-specific conditions like IBS, Crohn’s disease, and ulcerative colitis. Improving leaky gut improves these diseases[*].
Whey protein may help. In one study, patients with the inflammatory bowel disease Crohn’s saw improvements to leaky gut symptoms after just two months of whey supplementation. The improvement was similar to that experienced by patients given glutamine — a known building block for intestinal cells[*].
- Improved body composition: Supplementing whey helps you maintain more lean mass (as a % of total mass) — especially during weight loss[*].
- Weight loss during keto: Keto is an effective weight loss diet, and whey helps you maintain muscle during this process[*].
- Better metabolism: In diabetic and obese people, whey improves insulin sensitivity and blood sugar regulation[*].
- Muscle growth and recovery: Since whey is full of BCAAs, it’s the perfect protein for muscle synthesis.
- Preventing age-related muscle loss: Combined with resistance training, whey has been shown to mitigate sarcopenia[*].
- Immunity: Whey contains multiple immune-boosting compounds like beta-lactoglobulin, lactoferrin, and immunoglobulins.
- Antioxidant support: High in the amino acid cysteine, whey supports glutathione — your master antioxidant.
- Liver health: Whey shows promise for treating non-alcoholic fatty liver disease — a condition that affects 20-30% of people[*].
- Anticancer effects: Both cysteine and lactoferrin — whey compounds — appear to combat cancers of various types[*].
- Heart health: Whey supplementation has been shown to lower blood pressure in hypertensive people[*].
- Cognitive health: The tryptophan in whey, via the serotonin pathway, may support mental performance in times of stress[*].
- Gut health: Whey has been shown to improve leaky gut in people with Crohn’s disease[*].
Hopefully, these benefits are now firmly drilled into your head. Next: how much protein do you need?
How much protein, whey or otherwise, does a person need? Depends on the person, but science has given us clues:
Depending on your activity level, you’ll need more or less protein to support your daily needs[*].
- Very active: 150 grams protein for a 200 lb person (100 grams protein for a 140-pound person)
- Moderately active: 120 grams protein for a 200 lb person (80 grams protein for a 140-pound person)
- Sedentary: 90 grams protein for a 200 lb person (60 grams protein for a 140-pound person)
And older adults need to be even more vigilant about protein intake.
Protein is especially important as you age.
In one study, 387 healthy older women were grouped by two protein intakes: low and high. Low protein was below RDA (0.8 kg/pound body weight) and high was above RDA.
On follow up, the high protein women had lower body fat and a better lean mass ratio than low protein women. The high protein group also had better function in their upper and lower extremities[*].
The RDA, by the way, is only 51 grams protein per day for a 140-pound person. That’s not enough.
Bottom line? Go above the RDA for protein.
Pregnant women also need more protein to maintain muscle mass and support her growing child — around 1.2 g / kg bodyweight, and 1.5 g / kg bodyweight in the third trimester[*].
By now you’re probably wondering: can you take too much protein?
According to the research, up to 2 g / kg bodyweight protein per day is safe — while 3.5 g / kg bodyweight is the tolerable upper limit[*]. Also, people with a damaged liver or kidneys should exercise caution at high protein intakes[*].
Nothing here, of course, should be construed as medical advice. This guide is just a friendly resource.
Before reading this article, maybe you thought whey protein was only for power lifters, athletes, gym rats, and hulks. Maybe now you’ve changed your mind.
Whey, it’s true, has an impressive spectrum of health benefits. Want to maintain muscle while losing weight? Whey can help with that. How about mitigate disease risk, improve antioxidant defenses, and boost immunity? Whey can help with those things too.
If you’re still unconvinced, that’s understandable. Everything, including your daily protein powder, should be tested in the laboratory of your life. And if some other protein works better for you, then you should stick with that other protein.
But with so much supporting evidence, whey protein is at least worth a try. Because when you take a supplement every day, you want solid science behind it.