In the quest for bigger muscles, increased sporting performance and greater nutrient density many people turn to the world of supplements to seek the answer, particularly protein shakes. With the widespread knowledge that protein is necessary for muscular development it has been one of the mainstays of sports nutrition for many years. Often the increasing pace of life and lack of time to spend on cooking good food has caused athletes and recreational exercisers alike to seek out a convenient source of protein that can quickly and simply meet this need. This marketing niche has been dominated for some years by manufacturers of protein shakes and bars.
While it is true that powdered shakes and bars provide a solution for quick and convenient protein, it is just not as simple as gulping down a shake and here comes bulging biceps and rippling pectorals! The protein supplement market is overflowing with hundreds of different brands all claiming to be the best with a ‘proven’ track-record for achieving the most effective results. The sort of benefits and claims promoted tend to focus on protein density, product quality, ease of digestion, higher bioavailability, increased recovery, faster muscle growth and increased tissue density. It is quite likely that even the most committed bodybuilder, athlete or keen exerciser realises that some of the advertising used may push the boundaries of accuracy to some degree. If that is the case then what really makes a good protein powder and what should be avoided?
There are several different types of protein used within most brands. Animal based protein powders are usually based on dairy derivatives such as whey or casein, or from egg white albumin due to its high protein content. Plant-based protein powders are usually derived from pea, soya, hemp, or rice. These proteins vary in their biological value (BV) – which is the amount of consumed protein that is absorbed and incorporated into your cells. Most protein powders have strengths and weaknesses. Consider the following:
Rice protein (BV 83%) – Hypo-allergenic, gluten-free, neutral taste, economical. 100% plant-based. May be derived from genetically modified rice.
Egg protein (BV 100%) – Fat-free, concentrated amounts of essential amino acids. May upset stomach.
Milk protein (includes whey (BV 100%), casein (BV 77%), calcium caseinate, and milk protein blends) – May enhance immunity, high in BCAAs, contains lactose, highly studied. May cause digestive upset or other symptoms in people sensitive to whey, casein, and/or lactose.
Pea protein (BV 65) – No saturated fat or cholesterol, highly digestible, hypo-allergenic, economical. Rich in lysine, arginine and glutamine. 100% plant-based.
Hemp seed protein – Provides omega-3 fats, most forms provide fibre, free of trypsin inhibitors, can get in raw form, high in arginine and histidine. 100% plant-based. Biological value generally reported to be lower than most other protein powder sources.
Soy protein (BV 74%) – May have benefits for cardiovascular disease, contains some anti-nutrients, may be derived from genetically modified soy. 100% plant-based.
The most commonly used by far is still whey protein derived from milk, though the popularity of pea protein (derived from yellow split peas) seems to be on the increase with significant financial growth in this market being reported over the last 5 years. Whey is the liquid portion of milk left behind when the curds are separated in the process of making cheese or Greek yoghurt. Before the creation of protein shakes, whey liquid was an unwanted by-product of cheese manufacturer and was often disposed of in animal feeds, perhaps to the benefit of the livestock!
Whey is a highly bioavailable source of protein, rich in branched chain amino acids that are easily digested and quickly absorbed into the blood stream. This is one of the main reasons why it has been promoted so heavily for muscle growth and development. The problem is that whey protein only constitutes about 1% of whole milk. Whey proteins are in solution within the liquid water that is separated from the curds. This means that to get a significant amount of whey protein a large volume of bitter tasting, whey liquid would need be ingested, perhaps more than anyone would be prepared to take in a day. A quick thought at this point is if it is only present naturally in milk in very small concentrations why seek to ingest it much larger volumes? The problem of accessing large amounts of whey is the problem that the protein manufacturers have solved by concentrating and drying these sparse proteins into a concentrated powder, making it easy to ingest 20g or 30g of whey in one simple drink. Approximately 2 litres of milk would need to be consumed in order to get the same volume of whey. So how is it done? What manufacturing processes have been used to extract such a beneficial, elusive protein from milk for the convenience of the muscle seeking public?
There are several different techniques used to make a protein shake. They involve various separating, filtering and concentrating processes to remove the elements that are not wanted and keep the fractions of liquid that contain the sought after whey protein. Whilst it is unlikely all methods are used to make a single brand of powder the following processing options are available for use by the protein manufacturer:
- Ultra filtration, micro filtration, cross flow filtration and diafiltration
- Ion exchange
- Spray drying
- Freeze drying
A selection of these methods are used to produce virtually all varieties of whey protein on the market today including whey protein concentrates, whey protein isolates or hydrolysed whey proteins. Each of these processes places the fragile whey proteins at potential risk of physical change. Each process, bar freeze drying, exposes the whey to heat and pressure alone or both together at the same time. This can denature the whey protein molecules, which means it changes the proteins specific shape and structure. The higher and longer the heat is applied the greater the structural denaturation of the whey molecules will likely be. Some of the processing methods listed above use acidic chemicals, electrical current and enzymatic actions to separate out the whey proteins. These will also impact the whey proteins altering them from their natural form. Denatured proteins do still contain useable protein, but there is a risk that they may be less useful for the body and for some may even cause digestive distress altering the internal environment of the gut, which can be expressed within the body as bloating, gut irritation, flatulence or loose stools. Any protein powder or bar that causes any of these unwelcome side effects should be avoided as it may be a potential sign of a low quality, less effective product. It may also be a sign of low level digestive problems that may need to be more carefully addressed to return the gut to good health.
Some consumers may seek to avoid protein denaturation by purchasing ‘cold processed’ powders. The term implies that heat is not used in the processing of the whey liquid. This is simply not true. ‘Cold processed’ is a patented term that guarantees the powder has been produced with temperatures that do not exceed 50 degrees Celsius. This temperature was chosen because proteins become denatured more rapidly at temperatures above 55 degrees. Cold processing at these lower temperatures legally only needs to refer to the various filtering stages and does not mean that pasteurisation of the original milk has not occurred. Pasteurisation is a process that happens back within the jurisdiction of the original dairy that the whey liquid was sourced from. Milk is flash heated to 72 degrees Celsius for up to 30 seconds before the whey is separated from the curds. This means that some proteins will already be denatured before the filtering stages even begin. But does denaturing protein actually diminish the effectiveness of the shake in supporting muscle growth and repair?
We must still acknowledge that scientific research into most varieties of protein supplements for muscle growth does indeed show a positive result. Many of these studies compare the result of people taking a protein supplement to those who take no enhancing supplement. Differences in bodyweight have been observed across 12-18 weeks of supplementation and training that range from virtually nothing up to 4kg of lean mass. This suggests that taking a protein shake may not necessarily guarantee muscle growth, but is fairly likely to help in some way if the only change in diet was to take the protein powder. Interestingly scientific research that compares the results of taking regular whey protein to other sources of food protein is significantly more difficult to find. There are a few studies that provide an insight into how effective whey is in relation to results obtained using other proteins. In comparisons to casein protein (the curds), whey has been found to be absorbed quicker in the intestine, but casein ultimately stimulated more long-term muscle growth. This information has changed many protein formulations and it becoming more common to find whey and casein blends on the market today. Hang on a minute! Whey and casein blends? Isn’t that how nature packaged it to begin with – funnily enough we call that milk! Other areas of research into the volume of protein needed to stimulate muscle development has suggested that even active individuals probably get enough protein from a varied, whole food diet and that extra supplementation are not essential. Of course, this is not usually supported by the protein powder manufacturers who have invested large amounts of their own money to prove otherwise. Many individuals want to support muscle tissue in the most convenient way without the lengthy effort of addressing dietary change. There is no doubt drinking a shake 2 or 3 times a day is a simpler solution that trying to ensure daily diet is on point.
Whey and casein powders tend to be quite bitter and unpalatable on their own so often other ingredients are added to improve taste, texture, flavour, blendability and colour. Keep an eye out for artificial sweeteners like aspartame, saccharin, sucralose and acesulfame K to name but a few. Read the label and be discerning in your choices. There are many grades of protein powder on the market. If you are determined to use a protein shake, what quality of product should you be looking?
- Only purchase cold processed, pure whey protein concentrates – they may not contain as high a level of pure protein as isolates, but have been subjected to fewer stages of processing and are less likely to have suffered as much denaturation
- Try to determine the quality of the original milk the whey powder was manufactured from – organic, grass fed milk is best as it will not have pesticide, hormonal or antibiotic residues and if processed carefully may possibly have better overall nutrient value
- Avoid protein powders that contain added sugars, sweeteners, bulking agents, emulsifiers, preservatives, colours and flavours whether ‘natural’ or artificial
Perhaps the most important final thought is that supplementing with a protein powder will likely have little benefit if the total diet is not of good quality in the first place. Always include adequate amounts of high quality, naturally occurring foods that are rich in protein at every meal such as eggs, fish, meat, poultry, game, nuts, seeds, and protein rich pulses and legumes. Protein powders are, after all, a supplement, not a protein replacement.