Only Protein Protein Powder Review

Only Protein promises its Protein Powder fuels the body with 18 grams of clean protein per serving. On top of that, the company claims to use no harmful ingredients!

Only Protein says its products are organic, gluten-free, and all natural. It also comes in three flavors Only Protein promises taste great!

Does Only Protein Protein Powder deliver a good amount of protein? I decided to find out.

Inside the Powder

Only Protein Protein Powder contains a protein blend, protease, lactase, and many amino acids.

Protein Blend

The 27 g protein blend contains three milk by-products that all come from grass-fed cows: whey protein concentrate, whey protein isolate, and calcium caseinate. These ingredients all contain more than 90% protein.

In animal studies, whey protein concentrate enhances the immune system by increasing NK cell proportion in both epithelia and lamina propria compartments. [1]

In humans, whey protein isolate builds and preserves muscles, especially alongside amino acids like leucine. In one study, 15 subjects were given 15 g whey protein and 7.57 g essential amino acids. Results showed increases in skeletal muscle build and preservation. [2]

Calcium caseinate is valuable because it breaks down slower than whey protein, providing a sustained amino acid release. Calcium caseinate also prevents catabolism and preserves muscle. Because it is slow to digest, it creates a feeling of fullness. [3]

Out of the three protein forms, whey protein isolate has the most muscle-building potential. However, since the blend doesn’t list exact ingredient amounts, I’m not sure there is enough to be effective. Experts agree further research is needed on calcium caseinate and whey protein concentrate.


Only Protein Protein Powder contains 200 mg protease.

Protease is essential in breaking down and absorbing protein. It also relieves muscle soreness and strength. In one study, scientists gave 20 men protease and tested their strength in various areas. Strength increased by 7.6 % and recovery time was improved. [4]


Only Protein Protein Powder contains 200 mg lactase.

Lactase breaks down the sugar in milk, making Only Protein Protein Powder more digestible for lactose intolerant users. [5]

Essential Amino Acids

The essential amino acids in Only Protein Protein Powder:

• Isoleucine (1200 mg)
• Leucine (1980 mg)
• Lysine (1760 mg)
• Methionine (400 mg)
• Phenylalanine (640 mg)
• Threonine (1250 mg)
• Tryptophan (395 mg)
• Valine (1060 mg)

Essential amino acids are necessary for health, but they must come from diet because they aren’t produced naturally. Amino acids are building blocks for protein and are beneficial for building muscle.

In one study, six subjects randomly consumed either a drink containing 6 g essential amino acids or a placebo. After consumption, subjects experienced an increase in muscle protein anabolism and protein synthesis. [6]

A leucine-rich diet improves muscle protein synthesis and actually promotes fat burn while increasing lean muscle mass. [7] [8]

Doses of 1,000 to 2,000 mg lysine taken prior to bedtime increase lean muscle mass and promote anti-aging. [9]

Tryptophan increases serotonin levels, which enhances pain tolerance during exercise. In one study, tryptophan supplementation increased time to exhaustion by 80%. Amounts used in this study were not mentioned, and there are other studies that did not find the same results. [10]

Branched-chain amino acids (BCAAs) enhance exercise performance in some people. In one study, BCAAs (amount unknown) were given to participants in a marathon. Slower runners saw an improved time after taking BCAAs. However, faster runners saw no improvement. [11]

Nonessential Amino Acids

Below I will list all the nonessential amino acids and then go over the ones with the strongest links to exercise.

• Histidine (309 mg)
• Alanine (978 mg)
• Arginine (543 mg)
• Aspartic Acid (2020 mg)
• Cysteine/Cystine (478 mg)
• Glutamic Acid (3170 mg)
• Glycine (369 mg)
• Proline (1100 mg)
• Serine (884 mg)
• Tyrosine (614 mg)

Studies show nonessential amino acids are necessary nutritional supplements that encourage cell growth and overcome nutritional deficiencies. [12]

In one study, 13 males supplemented with an unknown amount of alanine for 10 weeks. During that time, subjects underwent a cycle capacity test to determine total work done. Alanine supplementation resulted in a 16.2% increase in total work done. [13]

Animal studies demonstrate arginine enhances growth and reduces fat content. [14] [15] In humans, 30 g arginine improves wound healing and enhances the immune system. [16] However, since Only Protein Protein Powder contains a fraction of the studied amount, this is not a likely effect.

In animal studies, 1 mg cysteine per kg body weight reduced insulin resistance, glycemia, oxidative stress, and markers of vascular inflammation. [17] Not enough human research has been done to determine cysteine’s benefits on exercise.

In humans, tyrosine improves cognitive performance. In one study, volunteers immersed themselves in cold water and consumed 150 mg tyrosine per kg. Tyrosine significantly improved cognitive performance after cold water induced stress. [18]

How to Use Only Protein Protein Powder

Only Protein Protein Powder comes in two forms: a 1.25 lb. tub and on-the-go sticks. For the tub, 1 scoop is 1 serving. For the sticks, 1 stick is 1 serving.

Mix 1 scoop or 1 on-the-go stick with 4-6 oz. of water and mix well. The on-the-go stick can easily be poured into a water bottle.

Customer Reviews

Customers on gave Only Protein Protein Powder an average 4.3/5-star rating. Customers on gave it 9.2/10. I wasn’t able to find any negative comments about this product. Here are some of the reviews:

“I use this product after my workouts and I take it on the go for a quick meal. I love how it taste but I am more impressed with how it is natural and sweetened with Stevia not an artificial sweetener. I also felt as though my recovery was faster after my workouts from using this brand versus other brands. Vanilla and chocolate are the only flavors I’ve tried. They taste great!” – jrpowell10

“Tastes pretty good and mixed well. The individual packs are a useful idea. Protein powder seemed to be on par with every other one I have tried. Overall a good purchase.” –cannonball123

“I have just started taking Only Protein and so far I LOVE it. I am all ways on the run and going from meeting to meeting and never get time to eat lunch on most days. Now that only protein has on the GO protein I dont ever miss a meal. I pack a water bottle with me and a bunch of Powder sticks in my brief case and all ways feel full. I don’t run out of energy through out the day. I feel better in the gym and love being able to maintain my body by taking multiple shakes a day. I use to take protein bars with me but they would all ways melt in my car and would end up being a waste of money.. Now I am becoming a health freak and this one the cleanest protein I have found and now its my favorite. Most clean proteins taste bad, But only protein taste great…. I recommend this to everyone I know…” –rippedupboys133

Possible Side Effects

Most of the ingredients in Only Protein Protein Powder are considered safe. Whey Protein is the only one that has side effects. These include:

• Nausea
• Thirst
• Bloating
• Cramps
• Reduced appetite
• Fatigue
• Headaches [18]


The best deals I found on Only Protein Protein Powder include:

• Only Protein: $39.99 per tub, $34.99 per stick package; order by calling 1.800.215.4324
• $39.99 per tub
• $32.99 per tub, $28.99 per stick package
• $27.99 per stick package
• $39.49 per stick package

GNC is the only Only Protein retailer with a money-back guarantee. Any product from can be returned within 30 days for a full refund.

About Only Protein

Headquartered in Draper, Utah, Only Protein was started by Mike Rino, Jesse Raddon, and Michelle (her last name wasn’t provided). These three founders were looking for a portable meal replacement that delivered a lot of protein. Together, they developed Only Protein.
No other information on Only Protein is available.

Final Thoughts

Only Protein Protein Powder is full of ingredients that support a healthy lifestyle. The protein blend contains a high amount of protein, as promised.

Customers seem happy with the product and especially appreciate the convenience of the on-the-go sticks. However, lack of information on the company makes me wonder if it is reliable. This looks like Only Protein’s first product, so I’m uncertain if the formula works.

If you are looking for a muscle-building, workout-enhancing protein powder, this product is probably not for you. This is more of a convenient way to get more protein in your diet. If you’re thinking about trying Only Protein Protein Powder, take advantage of GNC’s guarantee.


[1] Pérez-Cano, Francisco J., Silvia Marín-Gallén, Margarida Castell, María Rodríguez-Palmero, and Montserrat Rivero. “Bovine whey protein concentrate supplementation modulates maturation of immune system in suckling rats.” British Journal of Nutrition . Web. 9 July 2013.

[2] Katsanos, Christos S., David L. Chinkes, Douglas Paddon-Jones, Xiao-jun Zhang, and Asle Aarsland. “Whey protein ingestion in elderly persons results in greater muscle protein accrual than ingestion of its constituent essential amino acid content.”Nutrition Research (2008). Web. 8 July 2013.

[3] Karinch, Maryann. Diets Designed for Athletes. N.p.: n.p., 2002. Web. 8 July 2013.

[4] BECK,, TRAVIS W., TERRY J. HOUSH,, GLEN O. JOHNSON,, RICHARD J. SCHMIDT,, and DONA J. HOUSH,. “Effects of A Protease Supplement on Eccentric Exercise-Induced Markers of Delayed-Onset Muscle Soreness and Muscle Damage.” The Journal of Strength and Conditioning Research (2007). Web. 9 July 2013.

[5] Swallow, Dallas M. “GENETICS OF LACTASE PERSISTENCE AND LACTOSE INTOLERANCE.” Annual Review of Genetics (2003). Web. 8 July 2013.

[6] Rasmussen, Blake B., Kevin D. Tipton, Sharon L. Miller, Steven. E. Wolf, and Robert R. Wolfe. “An oral essential amino acid-carbohydrate supplement enhances muscle protein anabolism after resistance exercise.” Journal of Applied Physiology(1999). Web. 8 July 2013.

[7] Layman, Donald K. “The Role of Leucine in Weight Loss Diets and Glucose Homeostasis.” The Journal of Nutrition . Web. 8 July 2013.

[8] Rieu, Isabelle, Michèle Balage, Claire Sornet, Christophe Giraudet,, and Estelle Pujos. “Leucine supplementation improves muscle protein synthesis in elderly men independently of hyperaminoacidaemia.” The Journal of Physiology (2006). Web. 9 July 2013.

[9] “Meschino Health Comprehensive Guide to Accessory Nutrients and Essential Oils.” . Web. 9 July 2013.

[10] Williams, Melvin. “Dietary Supplements and Sports Performance: Amino Acids.” Journal of the International Society of Sports Nutrition (2005). Web. 9 July 2013.

[11] Blomstrand, , Hassmén, Ekblom, and Newsholme. “Administration of branched-chain amino acids during sustained exercise — effects on performance and on plasma concentration of some amino acids.” European Journal of Applied Physiology and Occupational Physiology (1991). Web. 9 July 2013.

[12] Lockart, Royce Z., and Harry Eagle. “Requirements for Growth of Single Human Cells “Nonessential” amino acids, notably serine, are necessary and sufficient nutritional supplements.” Science . Web. 9 July 2013.

[13] Hill, , Harris, Kim, Harris, and Sale. “Influence of β-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity.” Amino Acids (2007). Web. 9 July 2013.

[14] Kim, Sung Woo, Rebecca L. McPherson, and Guoyao Wu. “Dietary Arginine Supplementation Enhances the Growth of Milk-Fed Young Pigs.” The Journal of Nutrition (2004). Web. 9 July 2013.

[15] Fu, Wenjiang J., Tony E. Haynes, Ripla Kohli, Jianbo Hu, and Wenjuan Shi. “Dietary L-Arginine Supplementation Reduces Fat Mass in Zucker Diabetic Fatty Rats.” The Journal of Nutrition (2005). Web. 9 July 2013.

[16] Barbul, , Lazarou, Efron, Wasserkrug, and Efron. “Arginine enhances wound healing and lymphocyte immune responses in humans.” Europe PubMed Central . Web. 9 July 2013.

[17] Jain, Sushil K., Thirunavukkarasu Velusamy, Jennifer L. Croad, Justin L. Rains, and Rebeca Bull. “L-Cysteine supplementation lowers blood glucose, glycated hemoglobin, CRP, MCP-1, and oxidative stress and inhibits NF-κB activation in the livers of Zucker diabetic rats.” Free Radical Biology and Medicine . Web. 9 July 2013.

[18] “whey protein.” WebMD, n.d. Web. 8 July 2013.

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