Whey Protein is arguably the most popular food supplement available, largely because protein is the imperative for those looking to build muscle. Aside from the multitude of functions proteins have in the human body, they're also the key regulator/substrate for muscular (and other tissue) hypertrophy.
Needless to say, if you're putting in countless hours in the gym training then you're going to want to maximize your results by optimizing your protein intake.
Research continues to provide evidence that protein needs are greater in active individuals (especially those who lift weights regularly). Thus, many gym-goers find supplemental protein powders useful for meeting their protein demands.
What is whey protein?
All proteins are made up of amino acids, and whey happens to be a complete source of protein (meaning it contains all 9 essential amino acids that humans must obtain through diet). Whey protein remains readily soluble in liquid environments and over varying pH ranges and is denatured (unfolded) when treated with high heat.
Whey refers to the milk serum byproduct produced during the curdling of milk. Whey proteins comprise roughly 20% of the protein content in dairy milk, with the rest of being casein proteins. Whey proteins come in a variety of fractions, such as albumins and globulins, that vary according to the species from which they are secreted (dairy cattle produce milk that contains mainly alpha-lactalbumin and beta-lactoglobulin). Many dairy products, such as low-fat milk, cream, and cheese, are made by utilizing the functional characteristics of whey.
How whey protein is produced
Whey itself contains whey proteins, milk sugar (lactose), small amounts of fat, and micronutrients. Whey protein is filtered via one of several membrane filtration methods, such as microfiltration or ultrafiltration. After being filtered, the whey is spray dried and microencapsulated into a powdered product which may then be further altered by the manufacturer with specific food flavoring, coloring, etc.
Types of whey protein powders
- Whey Protein Concentrate (WPC) — Produced via ultrafiltration of whey, this refers to whey proteins that contain < 90% protein concentration, but could be as little as 20%. Usually, the exact proportion of whey will be notated following the term "WPC" such as WPC "75." The rest of the powder is comprised of lactose, fat, and micronutrients.
- Whey Protein Isolate (WPI) — May be produced by a variety of membrane filtration techniques, with the goal of reaching >90% protein concentration and removal of most (if not all) lactose. Manufacturers will also often combine filtration with an ion-exchange technique to selectively filter out particles by their ionic charge rather than just molecular size.
- Whey Protein Hydrolysates (WPH) — Whey protein hydrolysates are produced via enzymatic hydrolysis of either WPC and/or WPI. Essentially, this acts as a method of pre-digesting the protein by hydrolyzing (splitting) the protein's peptide bonds. The resulting product is rapidly digested and absorbed upon ingestion.
How whey protein works
Proteins are an essential macronutrient (meaning humans need to ingest them to survive) that are vital for many physiological processes, including neurotransmission, energy production, cardiovascular function, immune system regulation, and development and maintenance of muscle tissue. Amino acids are the building blocks of proteins, and proteins are subsequently the building blocks of muscle tissue since muscles are where the body stores most of its amino acids.
Whey protein is a complete protein with a large proportion of the amino acid L-leucine. L-leucine has been found to be a key substrate for stimulating the Mammalian target of rapamycin (mTOR) pathway which regulates muscle protein synthesis (MPS). Research corroborates that the proportion of leucine in a given protein source has implications on the peak MPS rate attained in the postprandial state.
There is a multitude of benefits from ingesting whey protein that stems from the biological role of essential amino acids and the list below summarizes the main benefits.
- Increases anabolic response to resistance training
- A complete protein source that is ideal for stimulating MPS
- Rapidly absorbed/digested
- Simple/convenient to add to one's diet
- Helps maintain muscle mass and prevent sarcopenia (muscular atrophy due to aging)
- Boosts immune system function in those who are physically active
- Protects lean body mass during prolonged aerobic activities
Which type of whey protein is best
In short, there is no "best" whey protein; choosing the right whey protein for you will come down to several factors including your budget, the quality/flavor desired, lactose tolerability, and what you are using the product for.
- Whey protein concentrate (WPC) — WPC is the cheapest priced whey protein supplement and tends to provide decent quality, making it a solid option for those on a tight budget. WPC is a bit higher in fat and carbohydrate content, though. There will be a small amount of lactose in most WPC products, so if you don't tolerate milk sugar very well then your best bet is to stay clear of WPC.
- Whey protein isolate (WPI) — If you want a lactose-free, low-fat, and easily digested protein then WPI is tough to beat. The main drawbacks to WPI are that it is relatively expensive and doesn't have the sweet, creamy texture that WPC does.
- Whey protein hydrolysate (WPH) — WPH is highly bioavailable, easy to digest, very low in fat and carbohydrates, and has a very high (>90%) protein concentration. Unfortunately, WPH tends to be the most expensive of all whey protein powders, but if you have the room in your budget then it's pretty much the "gold standard" of proteins.
- Whey protein blends — Most protein powder supplements are a blend of WPI and WPC, as manufacturers aim to create a balance between cost, flavor, and quality. Something to be wary of is companies that "label dress" their product by incorporating minute amounts of WPI and/or WPH just so it looks like they are giving you a higher quality product (when in reality, it's mostly overpriced WPC).
Whey vs. other protein sources
You're probably curious what is best/optimal when it comes to different protein sources (such as whey, casein, soy, egg, wheat, etc.). High-quality proteins such whey and casein are capable of promoting muscle protein synthesis post-exercise by activating the mammalian target of rapamycin (mTOR) signaling pathway. What this tells us, then, is that protein source does indeed matter, but only in the sense that you are ingesting sufficient essential amino acids (EAAs). Remember, EAAs are amino acids that we must obtain from dietary sources — humans can't synthesize them in the body.
Coincidentally, whey protein just so happens to be the ideal source of EAAs (per gram, that is), and most importantly, of L-leucine. Whey protein is also the most bioavailable source of protein for humans (meaning we readily digest and absorb it).
When to use whey protein
In reality, whey protein isn't a "supplement" so much as it is just a powdered food. It should be utilized whenever you are looking for a high-quality source of protein to add to your diet. That being said, research does show that taking whey protein pre- and post-workout can significantly enhance the MPS response to weight training.
How much whey protein should I use?
Research is ongoing as to how much protein is optimal (especially in active individuals). In general, it is recommended to ingest at least 1 gram of protein per pound of your lean body mass. Thus, an individual who is 10% body-fat and weighs 200lbs would aim to take in at least 180g of protein per day. Simply use your whey protein supplement accordingly to reach your protein goal for the day. If you're 'bulking' then, of course, your protein intake will be higher than average.
Whey protein FAQs
Q: I'm allergic to milk, is a whey protein supplement safe for me?
A: If you're only allergic to the casein fractions of milk, then whey protein supplements should be safe.
Q: I'm lactose intolerant, can I still use a whey protein supplement?
A: Yes, but whey protein concentrate supplements will likely contain the most lactose, so it may be in your best interest to invest in a pure whey protein isolate product.
Q: Does whey protein use have any side effects?
A: Whey protein is generally well tolerated by most individuals, but in special circumstances, there is the risk of certain side effects such as bloating/cramping/GI distress, increased bowel movements/flatulence, allergic reactions, and nausea/headache. These side effects can generally be easily alleviated by monitoring your total protein intake and making sure you are aware of any possible food allergies that you may have.
Q: Does it matter what liquid I use to mix my whey protein with?
A: No, the choice of liquid won't have any effect on the solubility (assuming it's not boiling hot).
Q: Does cooking/baking reduce the effectiveness of whey protein?
A: No, denatured protein is essentially "pre-digested" protein; you're still taking in all the amino acids that were originally in the protein, to begin with.
Q: Can I combine whey protein supplements with my other powdered supplements like creatine, glutamine, etc?
A: Yes, that's perfectly fine.