Editor’s Note: This is part of the Ultimate Guide to Protein. To answer all of your questions, I worked with the editors and researchers at Examine.com to put together the most comprehensive resource on protein, which answers all of your questions. If you missed Part I on “How Much Protein Do You Need,” please click here. Today’s topic: Protein powder sources. Enjoy the article, and feel free to post any comments or questions below.
By Kurtis Frank and Sol Orwell
With the endless supplemental protein options available, how do you know what’s best for you? Easy–just read this overview. It provides a breakdown of the benefits of each type of protein powder, and how it can work in your diet.
Whey protein is the most popular form of supplemental protein, and is derived from milk. During the process of cheese making, the milk is coagulated, which causes it to split into solids and liquids. This process is known as ‘separating the curds and the wheys’ (those that love poutine know all about cheese curds), and the ‘wheys’ (the liquid part) is literally whey protein.
In essence, whey is a synonym for water-soluble milk proteins. Of the protein extracted from milk, only 20% is whey (the other 80% is casein).
Whey is a complete amino acid source with moderate to high levels of most essential amino acids, but a relatively large amount of l-cysteine; the amino acid precursor to n-acetylcysteine and to the anti-oxidant enzyme glutathione. (Just making sure all you science nerds are awake and feeling excited.) Beyond the cysteine, whey protein also has some bioactive peptides that may reduce blood pressure (by acting as weak ACE inhibitors).
Whey is popular in part due to the mysticism of fast absorption being good for muscular gains. (Whether it is true or not, its practical benefits are far overstated by marketing. In other words: Yeah, it digests faster. And yeah, whey helps your muscles. But does the speed of digestion of whey make much of a difference to your body? Probably not.)
It was also once considered a waste product and thus cheap to procure. It has since greatly increased in demand, and is no longer as cheap. (As you can determine by walking into any supplement store and being able to blow your entire paycheck.)
The Bottom Line on Whey: Whey is derived from milk, and was originally a waste byproduct. It is (relatively) absorbed quickly by the body (with the importance of speed being vastly oversold), and it provides all essential amino acids.
Casein protein is milk protein minus the whey. Technically, casein protein refers to water insoluble proteins derived from dairy sources. It is the only other dairy protein, so if you are not consuming whey, you are consuming casein.
Casein is a complete protein source and its amino acid profile is relatively high in glutamine. It is touted as ‘slow absorbing’ due to its gel forming properties, which may either be your favorite thing about casein (pudding!) or your most hated, as it has really bad mix ability (not shaker-cup friendly).
The gel forming properties, although not providing too many health benefits, sets casein apart from other proteins merely from a practical standpoint. Casein protein inherently forms gels (which is why it has been used historically to make glue), and putting two scoops of casein into a bowl and adding a little bit of water makes pudding. (Eds note: It’s why I love BioTrust protein for my world famous Born’s protein ice cream. What? You don’t think it’s world famous? Try it first, and then get back to me.)
The physical properties of casein are novel, and allow protein powder to be made into different culinary spectacles. Using casein protein, you can enter a new world of protein cheesecakes and protein muffins (this can be done with other proteins like whey or rice, but you would need to purchase xanthan gum or glucomannan as gel-forming agents independently).
At least for some of your loved ones who may not like a healthy lifestyle, why not give them a chocolate cinnamon pudding that has the same protein and calorie content as two chicken breasts? Protein powders in general have come a long way in the flavoring department, and even then adding some at-home flavoring agents (blueberries, vanilla extract, etc.) can make some tasteful treats. But we digress.
Speaking of health properties, casein is not too remarkable when compared to whey. It does have a high calcium content (up to 60% of the RDA per scoop in some brands) but beyond that you won’t find any additional benefits. One important note: the allergic response tends to be far stronger with casein than whey. So if you have a dairy issue, you might need to lay off.
The Bottom Line on Casein: Casein is also derived from milk. Unlike whey, it has gel-properties, so that it thickens when mixed with water (pudding!). People allergic to milk should stay away from casein.
Soy is protein derived from the soybean (Glycine max) and is commonly included in supplements as well as food products because it’s a fairly cheap protein to produce. It seems to verge on the border of being a complete and incomplete protein source, with the methionine content varying depending on growing conditions.
Excluding other bioactives in soy protein (which we’ll expand upon later in another part of this guide, including the discussion on estrogenicity), the protein itself seems to be a decent source for supplementation. It does consist an adequate amount of amino acids, has a taste that is easily masked by flavoring agents, and can be processed in such a way that many undesired byproducts can be removed, making it a fairly pure solution of amino acids.
Although there isn’t sufficient evidence to support soy being ‘better’ than other protein sources, soy can act as a plausible alternative to dairy proteins assuming no allergies. (We’ll discuss hormonal issues in another section.)
The Bottom Line on Soy: Soy is a valid protein source. No better or worse than other sources in terms of amino acids and protein quality.
These two protein sources are bundled here due to their frequent usage together. Both protein sources are inherently vegan and both incomplete protein sources. But by adding them together in a balanced 1:1 ratio…ta-dah!…you have a complete vegan protein source.
Rice is a very thin and smooth tasting protein source low in lysine, while pea seems to have gel-forming properties similar to casein. It is possible that pea protein has as much versatility as casein protein when it comes to cooking due to these gel forming properties, while rice is likely to mix very well in solutions.
Additionally, rice protein is said to be low allergenic and is marketed to people with allergies to eggs, dairy, and soy. It seems to hold somewhat of a niche in this aspect.
Interestingly, the cumulative amino acid profile of a rice and pea combination (due to the high cysteine content of rice) is very similar to that of whey protein; due to this, a rice and pea combination formula is sometimes said to be a vegan source of whey protein.
The (quite limited) comparative studies suggest no significant differences between a rice and pea protein mixture when compared to other non-vegan sources.
The Bottom Line on Rice and Pea Protein: Rice and pea are independently incomplete sources. Combined, they are a complete source and they are good for people with allergies.
Egg protein is the protein fragment from egg whites, heat treated, and dehydrated into powder form.
It should be noted that there is a concern with eating raw egg whites. Here’s why (for all your Rocky lovers): a molecule known as avidin is an amino acid present in egg whites binds to the vitamin biotin, rendering the biotin unusable in your body. Although moderate raw egg white consumption is not associated with biotin deficiency, it has been reported in some isolated case studies where a few hundred grams of egg whites were consumed daily for a prolonged period of time.
Regardless, avidin is destroyed in the heat-treatment process, and is unlikely to be a concern in egg white protein supplements. The egg yolk tends to be excluded from protein powders due to being high in dietary fatty acids, and some leucine may be added to the egg white protein to make it more balanced (usually, leucine is found in the egg yolk).
Egg white protein can be useful to round out dietary protein needs, but it lacks enough evidence to support its usage over other protein powder sources. Additionally, there is a faint eggy taste that seems to persist over all but the strongest flavoring agents.
The Bottom Line on Egg Protein: As effective as any other protein, hard to see its benefits.
Beef protein is marketed to be a protein powder derived from dehydrated and processed beef (with the first beef protein on the market being blueberry flavour).
There is insufficient evidence to support the usage of beef protein, in any form, over other protein sources; especially when in the context of a mixed diet.
From a practical standpoint, the financial cost of dehydrating large amounts of meat into powders is exorbitant, and it is highly plausible that purchased beef protein is not beef protein in the sense of buying beef and processing it into a powder. Isolated amino acids can be put in a certain ratio to mimic complete protein sources, but this would exclude any particular meat-derived bioactive peptides. Essentially, there is a high chance your ‘beef protein’ is just glorified gelatin. Beef protein is new on the market and under-researched as a supplemental protein source.
In the end, beef protein is scientifically unsupported yet has a high probability of not being better than other protein sources, and it’s possible that it’s not actually beef. It would be better, and (probably) more delicious to eat the meat itself.
The Bottom Line on Beef Protein: Hard to see its benefits, especially considering its costs. We recommend you eat the real thing and skip the powders.
Hemp protein is a protein product derived from hemp seeds. To clarify:
For these reasons, hemp protein does not confer the same neural effects as smoking marijuana; the cannabinoid known as thc (tetrahydrocannabinoid) is not in sufficient quantities.
Hemp seeds are initially balanced in the three macronutrients (proteins, fats, and carbohydrates) and during oil extraction to produce hemp seed oil the residue left over is referred to as hemp meal or hemp seed protein. This byproduct is high in dietary protein on a weight basis (70-90% or so) and is used in hemp protein supplements.
Hemp protein is known to be high in both arginine and tyrosine relative to other protein sources, but is deficient in leucine and lysine; due to the insufficient amounts of lysine, hemp protein is deemed an incomplete protein source.
There are a variety of health claims associated with hemp, most of which are related to the oil portion (fatty acids in hemp seed protein are around 10% or less of overall calories) and due to how the oils are a fairly even balance of omega-3 to omega-6 fatty acids. The omega-3 fragment comes from alpha-linolenic acid (ALA), the same as in flaxseed, and not of the two omega-3 fatty acids found in fish oil (EPA or DHA). There are not too many studies using the oil portion in isolation, but nothing remarkable is noted with it relative to other fatty acid sources. Do note that ALA is not as easily-converted by your body as EPA and DHA are.
Although there is a lack of thc, there are other cannabinoids in hemp seed that do not have significant psychoactive properties (cannabidiol and cannabidisin B) but there is not enough evidence to suggest the minute quantities in hemp confer enough of these bioactives to exert unique health properties.
Hemp is not a bad protein source (consistently ranked lower than casein protein due to insufficient lysine and leucine contents), and there is indeed potential for the cannabinoids to exert some health effects. The magnitude of these health effects and whether dietary inclusion of hemp seed protein over other protein sources is relevant is not well studied, however.
The higher-than-normal dietary fiber content of hemp may be the most practically relevant deciding factor when purchasing hemp, as even the hemp seed meal is high in fiber.
The Bottom Line on Hemp Protein: Overall, a lack of evidence to support hemp as a superior protein source. The fatty acid portion is fairly overhyped and not too magical when in the context of a mixed diet, but the inclusion of dietary fiber might be an interesting point to consider when looking at hemp protein if there is a lack of fiber in your diet.
At the end of the day, worrying about the speed of digestion or any special properties of the various protein powders is an exercise in nit-pickery. Protein powders are meant to be a quick and easy solution for more protein, and all powders fit that criteria (although you saw our thoughts on meat powder). Your primary goal should be to eat as much protein as possible from whole food sources, and then meet your protein goals by using the supplements that work best for you to fill the gaps. Whether that means choosing convenience and taste (whey), cooking (casein), allergies (pea and rice, or egg protein), or cost (soy), there’s nothing magical about powders but each can serve a purpose and help.
And your health and fitness. If you’re still not sure what you should be eating or the best workout for you body, then apply for my online coaching and I’ll give you a call. (No joke.) You’ll receive a free consultation, and before you pay a cent, we’ll talk about your goals, how I can help, and if my program is the right fit for you. Sign up below and I’ll be in touch.