When you’re putting the time and hard graft into your training in the gym, it’s only natural to expect bigger and stronger muscles. Unfortunately, if you are not making the same effort in the kitchen by eating the right foods to support your training, then your results might not be as optimal as you would like. Protein Powder can help you bridge that dietary gap.
This means the right balance of the macronutrients carbohydrates, fat and protein. Unlike carbohydrates and fat, your body does not store protein, so it has no reservoir to draw from when you’re running low. This is why we need a constant supply of high-quality protein in our daily diets to achieve and maintain results.
The word protein comes from the Greek word ‘Protas’ meaning ‘of primary importance’, which highlights its importance as a fundamental ingredient in sustaining life.
Proteins were discovered by Swedish chemist Jöns Jakob Berzelius in 1838 and are among the most actively-studied molecules in biochemistry.
Proteins are formed by amino acids, of which there are twenty-two. There are nine of these that are known as essential amino acids (EAA), Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan and Valine, because our bodies can’t produce them, so it’s necessary that we include them in our daily diet.
Why do people drink protein shakes?
A good supply of protein is fundamental for any serious athlete as it’s important for repairing and rebuilding your damaged muscles after an intense workout. Research supports the conclusion that people who engage in regular exercise and sport require more protein, either in their diet or via supplementation than people who are sedentary. 
It also has the added benefit of making you feel fuller for longer, which stops you reaching for the sweet or fatty snacks.
Are all protein powders the same?
Protein comes from a variety of sources, including meat, milk, fish, and eggs, as well as beans, legumes, and nut butters. However, getting the amount you need to support a heavy training workload is not always that easy. Protein powders are synonymous with bodybuilding, though its benefits have spread to the wider athletic world as a way of getting high-quality protein. This is why the use of protein powders such as whey protein is a great option to supplement with.
What is protein powder? | The History of Protein Powder
The importance of diet in the bodybuilding world wasn’t important until Eugen Sandow, dubbed ‘The Father of Modern Bodybuilding’ advocated its importance in building muscle mass in the 19th century.
Sandow only took up bodybuilding to avoid joining the Germany military services in the late 19th Century. Instead, he moved to London and became a stage bodybuilder and co-wrote several early bodybuilding instruction books encouraging the consumption of ‘beef juice’ or ‘beef extracts’ to promote muscle growth and recovery.
In fact, he even went on to promote a product called ‘Plasmon,’ though details of the ingredients were difficult to find. The best guesses suggest it was some form of whey or egg white isolate.
In 1911, Sandow took his first real plunge into the supplement industry with the creation of ‘Sandow’s Health and Strength Cocoa’, which was a rudimentary protein drink similar to Plasmon.
Although the worth of protein supplementation was now established, it wasn’t until around 1950 that the first dissolvable protein powder was designed by eccentric nutritional chemist Irvin Johnson, who was considered one of the foremost bodybuilding nutritionists of the 1950s and 60s.
Johnson was a keen bodybuilder himself and owned a chain of gyms that allowed him to work with numerous young lifters and create his nutritional methods, which were similar to the ‘Ketogenic’ diet. This allowed him to develop his own products.
He created Rheo’s Protein Sixty, which was later called Johnson’s Protein and finally Blair’s Protein, as a result of Johnson changing his name to Rheo Blair, which is the more well-known name out of the two in the industry.
Blair Protein Powder was of higher quality than the earlier protein shakes and contained egg and casein protein, whereas most protein powders before this were made mostly out of egg, milk and soy.
When industry giants Bob Hoffman (York) and Joe Weider (Weider) became aware of how popular and profitable the market was, they quickly jumped on the bandwagon and began manufacturing and distributing their own branded versions of protein supplements.
The industry started to change in the late 80’s and early 90’s when people like the founder of Met RX, A. Scott Connelly came onto the scene. Scott Connelly had devoted his life to the science of nutrition and fitness and is considered a leading expert in the field of human nutrition and metabolism.
During his internship and residency at Harvard Medical School’s prestigious Massachusetts General Hospital, he began researching and formulating products to help prevent the loss of muscle mass for critically ill intensive care patients.
While continuing his research as a Senior Fellow in intensive care medicine at Stanford University, Dr Scott Connelly created a high-quality protein formulation, which he trademarked Metamyosyn. This became the key ingredient in MET-Rx that he went on to invent.
Met RX based their products on specific powder species and the amino acid profile of baby’s milk, believing that it is the closest to what nature gave to man.
The growth of protein powders has grown exponentially over the years and whether you’re an elite athlete or a weekend warrior, a vegan or a plant-based foodie, everyone is getting in on the protein trend. And with good reason.
According to strength and conditioning Charles Poliquin, leading nutrition scientists recommend a baseline of 1.6g of protein per Kg of weight. He also states that if you are involved in regular intense exercise, or looking to gain muscle mass or lose body fat with a low-carb diet then you may benefit from a higher protein intake. 
Protein Powder Benefits and Dangers
There is an abundance of protein powders on the market and it’s important to use them as part of a healthy eating and exercise plan, not as a single means to an end. So what are the pros and cons of using protein powders?
Protein Powder for weight gain
Convenience is the top benefit protein powders offer, though they have been shown to enhance lean muscle gain when combined with regular resistance training. Researchers at St. Francis Xavier University found that participants who supplemented a six-week weight-training program with whey protein gained more lean muscle and experienced greater strength gains than subjects who received a placebo. 
They are also;
- Easy to incorporate into meals & recipes (e.g. smoothies)
- Time-saving (can be consumed on the go)
- Shelf stability (does not require refrigeration)
- Drinkable (for those who struggle to eat whole foods after a workout or at other times)
Protein powder is a dietary supplement rather than a whole food, and as such, it can’t offer the same benefits as whole foods. Natural foods contain protective substances such as phytonutrients, antioxidants and dietary fibre, which cannot be reproduced in supplements like protein powder.
Can protein shakes damage your kidneys?
Taking protein powder when you’re already getting enough protein every day can lead to health issues such as nausea, cramps, fatigue, headaches and bloating. Over time it can damage your kidneys since they bear the brunt of metabolizing protein’s waste products.
When should you take Protein Powders?
One of the main marketed benefits of consuming protein powders and especially pre or post workout is due to a ‘magic window’ of opportunity where protein synthesis is greatest to enhance muscle growth and strength gains.
However, in 2013 researchers Alan Aragon, Brad Schoenfeld, and James Krieger were the first to investigate the effects of protein timing on muscle building and muscle strength in a meta-analysis. After contrasting and combining results from several randomized controlled trials, they concluded that current evidence does not appear to support the claim that immediate (≤ 1 hour) consumption of protein pre- and/or post-workout significantly enhances strength or muscles gains from resistance exercise. 
They also noted that the positive effects associated with protein timing seem to stem from a higher total protein intake throughout the day, rather than timed individual servings.
This notion of elevated sensitivity to protein actually lasts at least 24 hours. In fact, a 2012 review study by researchers at McMaster University showed that muscle protein synthesis may continue for 24 to 48 hours post-workout. 
It’s important to highlight that for sport-specific elite athletes and especially those that perform several workouts during the day, there may be variations to this. For most athletes, if you are consuming enough protein with the foods you eat, then your post-workout protein shake isn’t really essential.
However, if you’ve just finished a brutal workout and feel the need for some fast-absorbable energy, it’s probably a good idea to get some food into the system within a relatively short timeframe to kick-start the recovery process. Having to force 2 scoops of whey protein down if you’ve eaten a large mixed meal prior to training and aren’t really that hungry directly after your workout, just doesn’t make sense.
Quality of Protein Powders
It’s important to be aware that there are three main forms of protein powder that offer varying advantages.
The first and most common form is protein concentrates, which are produced by extracting protein from the whole food using heat and acid or enzymes. They typically contain about 60–80% protein, with the remaining 20–30% of calories from fat and carbs.
This is a cheaper option and can be harder to mix in liquid and digest, causing more bloating, gas and irritability.
Then there are protein isolates, which go through another filtering step that removes additional fat and carbs, further concentrating the protein. Protein isolate powders contain about 90–95% protein.
Isolate is technically better than concentrates, mainly due to digestion and mixability reasons. The protein quality and long-term benefits end up being essentially the same, though they are generally more expensive than concentrates.
Finally, there are Protein hydrolysates, which are also known as “hydrolysed protein.”
The raw protein source, whether its concentrate or isolate is further heated with acid or enzymes, which breaks the bonds between amino acids. This allows your body to absorb them more quickly, as they are essentially pre-digested.
Research has shown that hydrolysates appear to raise insulin levels more than other forms, which can enhance muscle growth response to exercise. 
Ultimately, all forms offer significant benefits. However, the differences often come down to what you’re willing to spend, and what kind of nutrition and protein loads you are looking for in your protein powder.
Measuring the quality of protein powders
There are two measurements that are worth noting when it comes to the quality of protein powders. They are the Biological values (BV) and the Protein Digestibility Corrected Amino Acid Score (PDCAAS).
The BV is a way to measure a protein’s “usability.” The higher the BV, the greater the proportion of available protein and a greater amount of amino acids that can be synthesized by the body’s cells.
Whey protein concentrate, for example, has a BV of 104. Whereas whey isolate has a BV of 100. Milk’s value is 91, and beef is 80.
You want a high biological value in your powders especially since their only reason for existing is to provide a quick, easy influx of dietary protein.
Interestingly, BV goes down with greater protein intake. Whey’s BV of 104 is at intakes of 0.2g/kg; it drops to around 70 at 0.5g/kg. This is why it is recommended to use protein powders sparingly to supplement your diet and focus on getting most of your protein from food.
Protein Digestibility Corrected Amino Acid Score
Protein Digestibility Corrected Amino Acid Score (PDCAAS), is a method utilized by the World Health Organisation and other government agencies to measure the quality of protein based on the amino acid requirements of humans and their ability to digest these protein sources.
The highest possible score being a 1.0. This score means, after digestion of the protein, it provides per unit of protein 100% or more of the indispensable amino acids required.
As a guideline;
- Pea Protein has a BV of 65 and a PDCAAS of 0.69
- Brown Rice Protein has a BV of 83 and a PDCAAS of 0.47
- Hemp protein has a BV of 87 and a PDCAAS of 0.46
- Egg White Protein has a BV of 100 and a PDCAAS of 1
- Casein Protein has a BV of 77 and a PDCAAS of 1
- Whey Protein has a BV of 1 and a PDCAAS 1
What are the different types of Protein Powder?
The protein powder market is constantly growing and there are more options now available than ever before, so finding the right product for the right situation can be confusing. So let me take you through all you need to know about the options available, allowing you to make the right decision to get the most bang for your buck.
Whey protein is amongst the top selling sports supplements in the world due to its ability to be digested quickly, making it the fastest acting protein compared to other protein sources.
Approximately 20% of the protein in cows’ milk is made up of whey. Whey is separated from milk as part of the cheese making process. During the cheese making process, the milk curdles (this is the casein) and the remaining liquid is known as Whey (also known as milk serum).
Whey protein is a complete protein naturally found in milk. It contains all of the essential amino acids needed for stimulating muscle protein synthesis. Whey is also rich in the three branched-chain amino acids (BCAAs), Leucine, Isoleucine, and Valine, which trigger protein synthesis and help build lean body mass.
Research at US Army Research Institute of Environmental Medicine (USARIEM) has shown that supplementation with whey protein powder is effective in improving muscle mass, strength, and aerobic and anaerobic power as the duration, frequency, and volume of resistance training increases. 
Many of whey protein’s purported health benefits are linked to a powerful antioxidant called glutathione. The body can make its own glutathione from the amino acid cysteine, and whey happens to be high in cysteine. Research has shown that hydrolysed whey protein isolate can increases glutathione in the body. 
Peas are a good source of protein. Protein powder extraction typically begins with green and yellow peas. They are ground into a powder and concentrated/purified by removing a majority of the carbohydrates, leaving a powder that in isolate form is approximately 85% protein, compared to whey isolate, which is 90%.
Pea protein is often overlooked because of concerns about its amino acid profile, digestibility, and taste, though the most important aspect of pea protein against other plant proteins is that it contains all nine essential amino acids. In particular, it is rich in Leucine, Isoleucine, and Valine.
Furthermore, Pea protein also digests slowly, which makes it perfect for taking before you go to bed. Evidence suggests that slower-digesting proteins are better for muscle growth over the long term due to how your body’s muscle-building machinery processes amino acids into muscle tissue. 
Researchers at the National Institute for Health and Medical Research (INSERM) in France have found that pea protein promoted a greater increase of muscle thickness compared to Placebo, and was as effective as whey protein. 
Pea protein is one of the unsung heroes among plant-based protein powders. It’s a great option for vegans and vegetarians, who often experience problems getting the right amount of protein from their regular diet. It’s also a good option for athletes who cannot digest most dairy-based proteins.
Casein is a protein found in milk. However, casein is digested and absorbed much more slowly than whey. This is due to one unique property of casein, and that’s its ability to clot, i.e. form a gel-like substance, in your intestines feeding your system with quality amino acids for hours. For this reason, casein protein is called “anti-catabolic.”
Research by the Department of Human Movement Sciences at the NUTRIM School for Nutrition in the Netherlands has shown that consuming casein protein has the ability to improve whole-body protein balance during post-exercise overnight recovery. [11)
Casein is 80% of the milk protein, while whey is 20%. It is a complete protein source and provides all the essential amino acids your body needs for growth and repair. Casein Protein is also rich in glutamine, an amino acid that aids recovery.
Brown Rice Protein
Typically, brown rice compliments protein as a carbohydrate due to the fact that it is low-glycaemic. But the fact of the matter is, brown rice is not naturally high in protein. However, when brown rice is processed and the carbohydrates are separated, you have a protein powder that is roughly 70% protein.
In fact, a 2013 Nutrition Journal study showed that brown rice protein is just as effective as whey protein in supplementing body composition and exercise performance! 
Brown rice protein contains more of the amino acid arginine than any other protein powder. Arginine is converted to nitric oxide in the body which helps to relax blood vessels and increase blood flow allowing for superior nutrient delivery to the muscles.
Brown rice protein is great for those looking to lose fat due to its high content of insoluble fibre. This, therefore, ensures you remain fuller for longer since both the high protein and high fibre content have been proven to help promote a greater feeling of satiety.
Furthermore, research conducted at the School of Food Science and Technology at Jiangnan University in China indicates that brown rice protein includes unique peptides that reduce weight gain more than those in soy protein. 
Alone, brown rice does not provide all of the nine essential amino acids that the body needs. That’s why brown rice protein powders often contain quinoa or chia proteins, which do have them, to compensate for what the brown rice lacks.
Although hemp is related to marijuana, it only has trace amounts of the psychoactive component tetrahydrocannabinol (THC). Hemp protein powder is made from the seeds of the hemp plant.
Hemp seeds are a powerhouse when it comes to protein with at least 20 amino acids, including the nine essential amino acids. Hemp protein absorption rate is comparable to casein, making it a great option for vegans and vegetarians.
It’s higher in most amino acids than brown rice protein. Finnish research has shown hemp to be high in arginine and tyrosine. Arginine is effective in boosting blood flow and tyrosine is effective in supporting cognition under stressful conditions. 
Hemp protein contains both soluble and insoluble fibre, the essential fatty acids omega-3 and omega-6 in a healthy 3:1 ratio.
Hemp protein consists of globulins (Edestin) and Albumin. These are two of the three most common types of proteins found in the human body, and hemp has more of these than any other plant-based source of protein.
Soy protein has been in the food chain for over 5,000 years. It is the only plant-based protein considered to be a high-quality protein, containing all of the essential amino acids needed to support growth and development.
The soybean is roughly 41% protein and is rich in branched chain amino acids, Lysine and Arginine. Lysine can help improve athletic performance, reduced stress and strengthen bones. Whereas Arginine is converted to nitric oxide in the body, which is responsible for opening up the blood vessels and encouraging better blood flow.
Researchers in Brazil found that postmenopausal woman who initiated in resistance training two to three times a week for 16 weeks while consuming a cup of milk with 25 grams of soy protein post-exercise made greater gains than women who only consumed a cup of milk. 
Soy protein due to its content of bioactive compounds, Isoflavones, has the ability to enhance athletic performance. Isoflavones can create an antioxidant effect, which results in quicker recovery, reduced muscle soreness and inflammation prevention.
Soy protein is a very popular dairy-free protein because it’s a complete protein, unlike many plant-based proteins powders.
When looking at sources of protein, there are many benefits associated with beef. First of all, it has all nine of the desired amino acid compounds your body needs.
Beef protein powder is one of the newest forms of protein powders available for athletes and fitness enthusiasts.
It has a digestion pattern that is slower than whey protein. In a shorter window, it shows smaller increases in protein synthesis than whey, though, over a longer period of 5 hours or more, it shows similar elevations in protein synthesis.
Actually, research has shown Beef Protein Isolate to be as effective as Whey Protein Isolate. 
Beef protein digests in your stomach instead of your intestines like whey protein, which makes it easier to digest and a good option for those who get bloated or gas from consuming whey protein.
Egg White Protein
Egg whites are well-known for being an excellent source of protein and contain all the amino acids including the 9 essential amino acids. According to a 2010 review published in the “Canadian Journal of Cardiology,” egg white protein is classified as a valuable, high-quality protein. 
Japanese researchers have shown that egg white protein supplementation with carbohydrate supplementation caused a significant increase in muscle strength in female athletes. 
Whereas whey is a fast-digesting protein, and casein is a slow-digesting protein. Egg-white protein falls somewhere in the middle.
Egg white protein contains as many as 40 different proteins, including ovalbumin and ovotransferrin. It is second only to whey protein as the highest source of the amino acid Leucine, which plays the biggest role in muscle health.
Pumpkin Seed Protein
Pumpkin seed protein powder is new to many people, yet offers quite a few benefits and advantages over other types of protein. It is loaded with dense nutrients and contains 18 of the amino acids.
Pumpkin is believed to originate from Northern America with earliest seeds found to be nearly 10,000 years old.
Pumpkin protein powder contains minimally 60% protein.
Pumpkin seeds are high in zinc, which is known to be very beneficial to your immune system and in the reduction of inflammation. Overall, pumpkin seed protein is similar to Hemp Protein in that high levels of healthy Omega-3 and Omega-6 polyunsaturated fats.
Pumpkin seed protein is a potent source of the amino acid L-arginine, which plays an important role in our body’s synthesis of nitric oxide. A double-blind and placebo-controlled study of men with Erectile Dysfunction found a “significant improvement” in the group using L-arginine. 
It also contains a number of minerals which include calcium, phosphorus, zinc, copper, iron, manganese, magnesium, and selenium. All are important for running metabolic pathways.
At first glance, the cranberry protein powder might not seem to compete well against other choices when considering the amount of protein content. A serving contains only about 25%. However, it is most often used in combination with other protein sources (hemp, rice, and pea protein are some of the healthier plant-based ones) to provide a desirable amount of healthy protein.
Cranberry protein isn’t made from cranberries at all. Instead, it’s made from cranberry seeds.
One of the amazing benefits of the cranberry protein is that it has a full amino acid profile, with a full serving of cranberry seed protein powder containing all 22 amino acids, including the 9 essential amino acids.
To make things even better, cranberry protein also has omega 3, 6, and 9 essential fatty acids. It’s also high in fiber, made up of as much as 20% soluble and 40% insoluble dietary fiber.
Protein Powder Blends
Protein blends are an effective way of using multiple sources of protein, as each protein powder has their own unique amino acid profiles and rates of digestion. Whey protein is naturally high in Leucine and is typically digested within 30 minutes. Egg white protein, on the other hand, is lower in Leucine, but higher in the amino acids Phenylalanine and Cystine, with a slower rate of digestion, so make a great combination.
A mixture of hemp and casein protein before going to bed to prevent muscle breakdown during sleep is effective. Whereas, for individuals who are lactose intolerant, a combination of rice and soy protein will provide an extra boost of protein.
Protein powders offer a quick and easy way to increase your daily intake. A fast-digesting protein such as whey is especially useful after training when you might not feel like sitting down to a proper meal.
But remember, total protein intake matters a lot more than protein timing. The “anabolic window” doesn’t close 30 minutes after a workout, and there’s no reason to force down protein shakes or food until you’re actually hungry.
- Campbell B1, Kreider RB, Ziegenfuss T, La Bounty P, Roberts M, Burke D, Landis J, Lopez H, Antonio J International Society of Sports Nutrition position stand: protein and exercise. https://www.ncbi.nlm.nih.gov/pubmed/17908291 Accessed on 22 May 2018
- The three rules of protein intake everyone should follow http://main.poliquingroup.com/Tips/tabid/130/EntryId/2387/The-Three-Rules-of-Protein-Intake-Everyone-Should-Follow.aspx Accessed on 22 May 2018
- Darren G. Burke Philip D Chilibeck K S Davidson Truis Smith-Palmer The Effect of Whey Protein Supplementation with and Without Creatine Monohydrate Combined with Resistance Training on Lean Tissue Mass and Muscle Strength https://www.researchgate.net/publication/224862544_The_Effect_of_Whey_Protein_Supplementation_with_and_Without_Creatine_Monohydrate_Combined_with_Resistance_Training_on_Lean_Tissue_Mass_and_Muscle_Strength Accessed on 22 May 2018
- Brad Jon Schoenfeld, Alan Albert Aragon and James W Krieger The effect of protein timing on muscle strength and hypertrophy: a meta-analysis https://jissn.biomedcentral.com/articles/10.1186/1550-2783-10-53 Accessed 18 May 2018
- N Santesso,1 E A Akl,1,2 M Bianchi,3 A Mente,1 R Mustafa,1 D Heels-Ansdell,1 and H J Schünemann Effects of higher- versus lower-protein diets on health outcomes: a systematic review and meta-analysis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3392894/ Accessed on 22 May 2018
- Power O1, Hallihan A, Jakeman P. Human insulinotropic response to oral ingestion of native and hydrolysed whey protein. https://www.ncbi.nlm.nih.gov/pubmed/18679613 Accessed on 22 May 2018
- Pasiakos SM1, McLellan TM, Lieberman HR The effects of protein supplements on muscle mass, strength, and aerobic and anaerobic power in healthy adults: a systematic review. https://www.ncbi.nlm.nih.gov/pubmed/25169440 Accessed on 22 May 2018
- Kent KD1, Harper WJ, Bomser JA. Effect of whey protein isolate on intracellular glutathione and oxidant-induced cell death in human prostate epithelial cells. https://www.ncbi.nlm.nih.gov/pubmed/12537959 Accessed on 22 May 2018
- Joost Overduin, Laetitia Guérin-Deremaux,2 Daniel Wils,3 and Tim T. Lambers NUTRALYS® pea protein: characterization of in vitro gastric digestion and in vivo gastrointestinal peptide responses relevant to satiety https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4400298/ Accessed on 22 May 2018
- Nicolas Babault, Christos Païzis, Gaëlle Deley, Laetitia Guérin-Deremaux, Marie-Hélène Saniez, Catherine Lefranc-Millot, and François A Allaert Pea proteins oral supplementation promotes muscle thickness gains during resistance training: a double-blind, randomized, Placebo-controlled clinical trial vs. Whey protein https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4307635/ Accessed on 22 May 2018
- Res PT1, Groen B, Pennings B, Beelen M, Wallis GA, Gijsen AP, Senden JM, VAN Loon LJ. Protein ingestion before sleep improves postexercise overnight recovery. https://www.ncbi.nlm.nih.gov/pubmed/22330017 Accessed on 22 May 2018
- Joy JM, Lowery RP, Wilson JM, Purpura M, De Souza EO, Wilson SM, Kalman DS, Dudeck JE, Jäger R The effects of 8 weeks of whey or rice protein supplementation on body composition and exercise performance. https://www.ncbi.nlm.nih.gov/pubmed/23782948 Accessed 22 May 2018
- Zhang H1, Bartley GE, Mitchell CR, Zhang H, Yokoyama W. Lower weight gain and hepatic lipid content in hamsters fed high fat diets supplemented with white rice protein, brown rice protein, soy protein, and their hydrolysates. https://www.ncbi.nlm.nih.gov/pubmed/21913675 Accessed on 22 May 2018
- C. Callaway Hempseed as a nutritional resource: An overview https://link.springer.com/article/10.1007/s10681-004-4811-6 Accessed on 22 May 2018
- Fábio Lera Orsatti, 1, 2, 3 * Eliana Aguiar Petri Nahas, 1 Jorge Nahas-Neto, 1 Nailza Maesta, 2 Cláudio Lera Orsatti, 1 and Cesar Edurado Fernandes 4 Effects of Resistance Training and Soy Isoflavone on Body Composition in Postmenopausal Women https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2872758/ Accessed on 22 May 2018
- Matthew Sharp,1 Kevin Shields,1 Ryan Lowery,1 Jason Lane,1 Jeremy Partl,1 Chase Holmer,1 Julie Minevich,1 Eduardo De Souza,1 and Jacob Wilson The effects of beef protein isolate and whey protein isolate supplementation on lean mass and strength in resistance trained individuals – a double-blind, placebo-controlled study https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4595383/ Accessed on 22 May 2018
- One egg yolk worse than some fast-food meals when it comes to cholesterol, Canadian physicians say https://www.sciencedaily.com/releases/2010/11/101101142515.htm Accessed on 22 May 2018
- Azumi Hida,1 Yuko Hasegawa,1 Yuko Mekata,2 Mika Usuda,3 Yasunobu Masuda,3 Hitoshi Kawano,4 and Yukari Kawano1 Effects of Egg White Protein Supplementation on Muscle Strength and Serum Free Amino Acid Concentrations https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3497008/ Accessed on 22 May 2018
- Chen J1, Wollman Y, Chernichovsky T, Iaina A, Sofer M, Matzkin H. Effect of oral administration of high-dose nitric oxide donor L-arginine in men with organic erectile dysfunction: results of a double-blind, randomized, placebo-controlled study. https://www.ncbi.nlm.nih.gov/pubmed/10233492 Accessed on 22 May 2018