What is Whey protein?
Whey protein has gone mainstream due to its popularity among the fitness community. It is the protein of choice because it is cheap, quick to consume and its benefits are backed by research.
Resistance training combined with high protein intake improves strength, muscle gain and helps in weight loss.
Whey protein is a dairy protein. Milk protein is composed of two types of proteins: Casein and Whey.
Casein makes up about 80%, whereas Whey constitutes about 20% of the total milk protein. Whey protein is considered superior protein compared to casein because of the amino acid composition (1).
Milk proteins are isolated when milk is treated with acid or rennet.
It separates casein from whey. Casein precipitates to the bottom whereas whey is the aqueous part (2). Further processing creates what we know as whey protein powder.
Whey protein composition
The quality of protein depends on its amino acid composition. Whey protein contains essential branched-chain amino acids (BCAA) (3).
3 amino acids are considered BCAA.
- Leucine
- Isoleucine, and
- Valine
BCAA and especially Leucine is important for skeletal muscle development (4).
There are some amino acid differences between whey and casein. For example, compared to whey protein, casein has a high concentration of proline amino acids (5).
Whey protein contains many important biological compounds (6).
It is composed of:
- Beta-lactoglobulin
- Alpha-lactalbumin
- Lactoferrin
- Glycomacropeptide, and
- Immunoglobulins
Beta-lactoglobulin influences the immune system, therefore, has implications for infections and disease (7).
Glycomacropeptide of whey has a satiety effect. It is also good for the management of phenylketonuria (8).
Lactoferrin has immunological properties. It also has antibacterial and antiviral properties. Recent studies show that lactoferrin may prevent SARS-CoV-2 from binding to human cells (9). However, the lactoferrin concentration in whey protein may not be adequate to prevent or treat covid-19.
What are the types of whey protein?
There are 3 types of whey proteins available in the market (10).
- Whey protein concentrate (WPC)
- Whey protein isolate and (WPI)
- Whey protein hydrolysate (WPH)
Whey protein concentrate consists of fats and lactose with amino acids. The whey concentrate can be beneficial in enhancing the glutathione (GSH) antioxidant system as well as antitumor activity (11).
Compared to whey concentrate which is 80% protein, whey protein isolate is 90% protein (12).
Thus, whey protein isolate provides more protein for the same quantity. Because isolates have higher protein content, they can cost more compared to whey concentrate.
Finally, whey protein hydrolysate is made by hydrolysis of proteins. This converts long-chain amino acids into variable-length peptides.
Hydrolysate is shown to be superior to casein, a slow-digesting protein, in promoting muscle strength and lean body mass. Moreover, protein hydrolysate is better for recovery after resistance training because small peptides are rapidly absorbed in the body (13,14,15).
What are Whey protein Benefits?
There are several benefits of whey protein. Some of the most important ones are highlighted below.
Whey protein can help with weight loss and obesity
Nutritional interventions are considered one of the most important ways to weight loss and obesity control.
Both animal and human studies have shown that a low-calorie diet and a high protein intake are helpful in weight loss.
In animals, the use of microfiltered native whey protein has been shown to significantly improve weight loss (16).
In humans, the use of whey protein on a low-calorie diet accelerated weight loss (17).
Lactoferrin in whey protein is considered to be responsible for whey mediate weight loss. Lactoferrin is also shown to prevent weight regain after a weight loss diet regime (18).
Studies in animals and humans have shown that whey protein promotes weight loss and obesity control on low calorie-diet.
Whey protein aids in resistance training muscle development
Whey protein is efficient in recovery after resistance training. Many studies have shown that whey protein consumption with resistance training helps lean muscle mass development.
Research in animals shows that whey protein is better than casein in muscle recovery after injury (19).
In humans, compared to soy protein, whey protein was superior in muscle protein synthesis due to higher leucine concentration and better protein absorption (20).
The timing of whey protein intake is also important. The intake of whey protein around resistance training was the determining factor for lean muscle mass development instead of the total amount of protein taken (21). Thus, taking whey protein after or before resistance is beneficial for muscle protein development.
Whey protein use is associated with lean muscle mass development and recovery after resistance training. The consumption of whey protein around resistance training is better for muscle development.
Whey protein has anti-oxidant and anti-inflammatory properties
Whey protein has components that confer anti-inflammatory properties.
The use of whey protein was effective in lowering the C reactive protein levels in cystic fibrosis patients. The increased antioxidant function is attributed to increased glutathione levels after whey protein consumption (22).
Whey is important for building antioxidant capacity most likely due to the presence of cysteine amino acids (23).
Cysteine-rich whey isolates are shown to increase total antioxidant capacity (24).
Whey protein hydrolysate has been shown to impart antioxidative properties as well (25).
In animal studies, whey protein amino acids (cysteine and threonine) were responsible for anti-inflammation due to an increase in microbiota proliferation (26).
A rat liver inflammation model study shows that the use of whey protein significantly reduced inflammation (27).
In humans, enteral Whey protein formula administered to ischemic stroke patients significantly reduced inflammation indicator IL-6 and increased glutathione levels (28).
Finally, in a study in patients with chronic obstructive pulmonary disease, whey protein peptides use decreased inflammation and exercise tolerance in patients (29).
Studies in animals and humans have shown that whey protein use promotes anti-inflammation and antioxidation.
Other health benefits of Whey protein
Enhanced immune system: Whey protein use is associated with increased immune response by animal and human studies (30). Glutotheionin has been implicated in enhancing the immune system (31).
Whey protein and diabetes: Whey protein amino acids leucine, isoleucine, valine, lysine, threonine can increase insulin levels compared to simple carbs (32). Cysteine is of particular interest because it can significantly increase insulin levels (33).
Phenylketonuria management: Phenylketonuria is a condition in which patients cannot assimilate phenylalanine amino acid. Whey protein Glycomacropeptide is low in phenylalanine and therefore an excellent protein source (34).
Whey protein and blood pressure: Whey protein can lower blood pressure because it has been shown to improve arterial dilation (35). Whey protein intake with resistance training increases HDL levels. HDL is considered good cholesterol (36).
Whey protein and cancer: Whey protein may also protect against cancer. Whey protein isolate could suppress the proliferation of tumor cells (37). Lactoferrin use was shown to attenuate colorectal polyps by improving TNF-alpha (38). More studies are needed to explore whey protein effects on tumor cells.
Whey protein safety and risks
Are there dangers of whey protein use? A recent comprehensive meta-analysis of several studies found no adverse effects after the use of whey protein. Whey protein is generally recognized as a safe source of protein(39).
People who have issues with milk products may encounter digestive problems such as diarrhea and stomach bloating after the use of whey protein. Moreover, low-quality whey from unreliable manufacturers may also cause stomach upset.
Studies regarding digestive issues are not very clear.
One study tested the long-term use of whey protein and found that whey protein use may alter the gut microbiota and have harmful effects on the proliferation of gut microbes (40).
Contrarily, other research shows that whey protein use has prebiotic effects and may promote desirable gut microbes called probiotics (41).
More studies are needed to definitively understand the effects of whey protein on gut microbiota.
High protein consumption may have deleterious effects on kidney function.
However, recent data suggest that a diet high in protein does not pose risk to kidneys. But for an existing kidney problem, a low protein diet may be needed (42,43).
Animal studies have shown that a high protein diet may be harmful to kidneys but adding resistance training has a protective function (44).
A similar animal study found that long-term excessive whey protein use may cause liver damage but animals that followed resistance training were protected from liver issues (45).
In summary, current research suggests that whey protein is safe to consume. The deleterious effects of high protein consumption can be minimized by following resistance training programs.
How to take whey protein?
Whey protein can be easily consumed by mixing it with water or milk. No special equipment or gear is needed. Please read the serving information and instruction carefully. Many people add whey protein powder to their smoothies or make protein shakes after workouts.
Frequently Asked Questions (FAQs)
Does whey protein cause cancer?
So far no published study has observed whey protein as a cause of the development of cancers. In fact, a few studies reported the anti-tumor potential of whey protein due to be the presence of lactoferrin in whey protein.
How much whey protein per day?
Many people wonder if “2 whey protein scoops ok?”
Excess of everything is bad. Whey protein should not be considered a meal replacement. It’s a dietary supplement that gives a boost in muscle synthesis.
Current research shows that to maximize muscle growth, an intake of 0.4 g/kg of body weight /meal across a minimum of 4 meals per day is desirable. This will provide a minimum of 1.6 g/kg of body weight /day of protein
It is commonly recommended to consume 20-25g of high-quality protein per meal.
Thus, whey protein at a minimum of 20-25g of protein should be consumed mostly around workouts (46). The rest of the protein requirement for the day may be taken via other sources of proteins.
For example, an individual who weighs 70 kg should consume a minimum of 28g of protein per meal.
What are alternatives to whey protein?
Whey protein is a fast-absorbing and convenient source of protein. It helps muscle building but it is not the only source of proteins. There is slow absorbing milk protein e.g. casein. Traditional animal and plant-based proteins should also be used in your diet. Some examples are:
Meat
Pork
Poultry
Beans
Tofu
Lentils and chickpeas
What is the best Whey protein?
A high-quality whey protein should be least processed and should be low in sugar. Whey protein should also be free of toxins and contaminants.
Buy whey protein from trusted sources with good manufacturing practices.
As far as the type of whey protein is concerned, whey isolate, concentrate, and hydrolysates have shown excellent results in muscle growth and lean muscle mass development.
Combining resistance training + whey protein with BCAA and a high leucine content i.e. 3g is ideal for muscle protein synthesis(47,48).
What whey protein to use for weight loss?
There is no specific whey protein type that can help with weight loss. Research shows that whey protein use with a calorie-restricted diet combined with resistance training can significantly help with weight loss (49).
When should whey protein be taken?
Whey protein should be taken around resistance training sessions. Research shows that the use of whey protein post-workout is best for muscle development (50).
Will whey protein make you fat?
No, to date no study has shown obesity or fat gain as a potential side effect of whey protein use. Studies have shown that whey protein can help you lose weight when combined with resistance training and calories restriction.
