Rule 1 Protein Review & Side Effects: Is Rule 1 Protein Good?

by Joe Costello, CNC | Protein Powders

Rule One Protein Powder Review

Rule One Protein Powder (R1 Protein) is made by the same people who created Optimum Nutrition and the legendary Whey Gold Standard. In this Rule 1 Protein review, we will take an in depth look at this product and determine its effectiveness, taste and overall value.

However, before we dive into the review, allow me to save you bottom-line chasers some time. Rule One Protein is simply not worth the price. That’s what it really comes down to for me. The formula is great, but it’s not particularly outstanding, which means the high price point is not justifiable in my view.

Additionally, I have a significant concern about the whey protein blend. It does not contain any plant based or vegan protein sources…it strictly uses whey protein derived from animals, which recent studies show can cause all sorts of side effects with regard to digestive health and gastrointestinal function.

Be sure to check out our list of the Best Protein Powder Supplements to see some products that are ranked higher.

Rule 1 Protein review: Is Rule 1 Protein good?

R1 protein powder is a pretty solid product due to their extremely clean whey protein blend. The protein blend consists of strictly whey protein isolate and whey protein hydrolysate. This makes the protein fast acting and effective, but it leaves questions with regard to digestion and absorption. Recent studies have shown that plant-based protein sources are much more efficiently digested.

So, is Rule 1 Protein good? As a Certified Nutrition Coach with over 10 years of experience in this industry, I would answer this question with a yes, but I would also say that this is a product I’d never recommend to my clients. It’s not that there’s anything wrong with Rule One Protein, it’s just that plant-based protein has proven to be SO much more effective that I have a hard time recommending any whey protein products at this stage in my career.

Personally, I take a protein powder called VegaTein every day after my exercise routine. VegaTein is 100% natural, plant-based, vegan protein powder. It packs a powerful 20 grams of protein per serving, and you can rest easy at night knowing every gram is getting properly digested and absorbed since all of the protein comes from plants. That means it contains no dairy, no soy, no lactose, and no GMOs.

Rule 1 Protein discount code: Are there any current Rule 1 protein deals?

There is not currently an active Rule 1 Protein discount code available. Unfortunately, we were unable to locate a coupon code, but we wouldn’t recommend the product even if we had a coupon code to be honest. It’s a very solid protein powder, but our top ranked options are much better.

What is the Rule 1 Protein best flavor? Choose from this list:

Rule 1 Protein comes in a bunch of different flavors, and as an avid user of their supplements, I have tried just about every one. For me, the Rule 1 Protein best flavor is chocolate, but here are some of my other favorite flavors:

  • Chocolate Fudge
  • Chocolate Peanut Butter
  • Lightly Salted Caramel
  • Strawberries & Cream
  • Frozen Banana

Rule 1 Protein ingredients list

The Rule 1 Protein ingredients are:

  • Whey protein isolate
  • Whey protein hydrolysate
  • 6 grams of BCAAs per serving
  • Glutamine
  • Valine
  • Isoleucine
  • Leucine

Whey Protein Isolate

Whey Protein Isolate is the purest, fastest digesting, and most efficiently absorbed form of protein available. The most commonly used protein source is whey protein concentrate, but concentrate is significantly less pure and has a very high fat content. Whey protein isolates are the purest due to the fact that they have undergone the process of Cross-flow Micro-filtration, which purifies the protein and filters out unhealthy ingredients.

Whey Protein Hydrolysate

Whey Protein Hydrolysate is actually just hydrolyzed whey protein isolate. This means that the purification process has been taken a step further with hydrolysate. Whey protein hydrolysate is made when the whey protein has undergone both Cross-flow Mirco-filtration and Enzymatic Hydrolysis. Enzymatic Hydrolysis breaks the protein particles down into tiny little pieces for maximum digestion and absorption.

BCAAs (branched chain amino acids)

R1 Protein is absolutely jam packed with BCAAs, which can allow you to experience muscle growth and recovery much faster. And when we say jam packed, we mean JAM PACKED. There are over 6 grams of 18 different BCAAs in every serving.

In addition to aiding growth and recovery, BCAAs also support fat loss by encouraging your body to use body fat for fuel during your workouts rather than muscle. This large of an amount of BCAAs can help you burn fat and replace it with lean muscle every time you follow up your workout with a Rule 1 Protein shake.

Your muscles can also be much less sore after your workouts due to the potentially increased recovery rate, in addition to the fact that your workouts themselves can be much more productive due to the increased levels of strength and endurance the BCAAs can allow for. One can not understate the importance of amino acids when it comes to muscle growth and recovery. Amino acids are the building blocks of muscle…never forget that.


R1 Protein also contains exceptionally high levels of Glutamine, which is a great ingredient for the improvement of protein metabolism. Glutamine is also known to be amazing for supporting human growth hormone (HGH) levels. Glutamine is absolutely vital in order to get as much out of your workouts as possible because an increase in HGH levels could mean an increase in muscle growth.

Rule 1 Protein nutrition facts

Rule 1 protein nutrition facts

Above is an image of the very impressive supplement facts panel, but we will further illustrate the Rule 1 whey protein nutrition facts in the table below…

Rule 1 Protein Nutrition Facts

Amount Per Serving

Whey protein

25 milligrams



Total Fat

0 grams


5 milligrams


50 milligrams


1 gram


0 milligrams

Branched chain amino acids (BCAAs)

6 grams



Artificial preservatives


Protein purity percentage (PPP)

87% (industry leading)


120 milligrams


270 milligrams

Rule 1 Protein benefits

Due to the nature of the blend, there are a ton of potential Rule 1 Protein benefits users can expect to experience. Each serving contains 25 milligrams of pure whey protein isolate/hydrolysate, which can lead to enhanced muscle growth, recovery, and weight loss.

There are 3 major problems with most protein powders that are often overlooked.

First, almost all of them contain excessive amounts of unwanted ingredients. Among these are fat, sugar, carbohydrates, cholesterol, gluten, lactose, and added creamers. These ingredients are very detrimental to your health and will cause you to gain fat. Rule One Protein is one of the only protein powders that contains zero fat, zero sugar, zero lactose, zero gluten, zero added creamers, only one gram of carbohydrates, and only five milligrams of cholesterol.

Secondly, almost every single protein powder out there uses forms of protein that lack purity, such as whey protein concentrate. Ideally, a protein powder formula should use strictly either whey protein isolate or whey protein hydrolysate, which are the purest forms of protein in existence. A pure and clean formula can allow for lean muscle gain, and can eliminate the risk of gaining fat. Rule One protein is one of the only protein powders on the market that uses strictly whey protein isolate and whey protein hydrolysate.

Lastly, the vast majority of protein powders don’t contain a sufficient amount of BCAAs due to the impurity of their blends and use of inferior protein sources. It is of vital importance that you understand how crucial a high concentration of BCAAs is in order for the protein powder to be effective.

Regular whey protein in itself can obviously aid in muscle recovery, but your muscles can not fully recover or grow without a sufficient supply of BCAAs. BCAAs are necessary for muscle growth and recovery. A protein powder that does not contain enough naturally occurring BCAAs can be extremely less effective. Rule One contains over 6 grams of BCAAs in every serving (including glutamine, valine, leucine, isoleucine, and many more), which is among the highest we have seen.

Rule 1 Protein side effects

It’s very possible you may experience Rule 1 Protein side effects including upset stomach, stomach pain, digestive issues, and irritable bowel movements. The reason there is a real risk of these side effects occurring is because of the product’s use of whey protein. The protein blend relies entirely on whey protein, which means it contains dairy, lactose, and soy, all of which are known to cause gastrointestinal side effects. Here’s some more info on the health problems that whey protein can cause…

Whey Protein Consumption

Okay, this is the part where I will go in depth on the negative effects of consuming whey protein. Whey protein is an animal product. Most whey proteins and milk proteins comes from cows. What this means is that when you are consuming whey protein, you are also consuming high levels of dairy, lactose, and soy. If you have a sensitive stomach whatsoever, you’re going to have an issue when consuming whey protein. It’s really that simple.

The solution to this problem is to avoid whey protein consumption and instead opt for plant-based protein sources like Pea Protein. Pea Protein is what I personally use, and it is fantastic. I have a very sensitive stomach, and it causes no s stomach issues for me. The health benefits have also been amazing. With Pea Protein, I get amazing results with regard to muscle growth and recovery, but it also is very soothing on my stomach and helps improve my gut health.

Inefficient digestion and absorption are two of the biggest problems that come with consuming whey protein. Ever since I switched to plant-based proteins, my gut health has improved drastically. Vegan protein is just way easier on your stomach and can produce a wide array of other health benefits outside of just muscular growth and recovery.

There is also a common misconception that the positive effects of whey protein such as muscle building can not be experienced with plant based protein sources…this is simply not true. With plant based protein powders, you can reap all of the positive effects of whey protein without having to deal with any of the side effects of whey protein…it’s truly life changing.

Another misconception is that plant proteins don’t have as many amino acids…this is just plain wrong. The 100% plant based protein powder I use provides 9 essential amino acids and significantly increases my daily protein intake in a very healthy and efficient way. These amino acids help drastically with the process of muscle building, and I would never take a protein powder that does not contain a sufficient amount of them. Amino acids are the building blocks of muscle!

Other Rule 1 Protein cons

The only real down side to Rule 1 Protein is the fact that it costs a few extra bucks per jar compared to the standard protein powder, but there’s a reason it costs extra. You get what you pay for, and that’s especially important when it comes to supplements or anything else you put into your body. Plus, the discount code we provided should help with the price.

Rule 1 Protein complaints & praise (from real customer Rule 1 Protein reviews)

Currently, there are over 2,000 Rule 1 Protein reviews on Amazon, and the data is extremely impressive. Out of 100 total customer reviews, it received an average rating of 4.7 stars out of 5, which is exceptionally high and well above average.

Perhaps even more impressively, 87% of the R1 Protein reviews contain 5 star ratings. That means 87 people tried it and liked it so much, that they went back on to Amazon to give it a 5 star rating. That’s a lot of effort, so this is usually a very good indicator that people are very happy with the product.

The data from these Rule 1 protein isolate reviews is overwhelmingly positive and reaffirms our theory that R1 protein is extremely effective.

Is Rule 1 a good brand?

Rule 1 is a very good brand. Pretty much every product they make is very well formulated and qualifies as top shelf. Their protein powder is what they are most known for, which makes sense because it is their best product. We just wish they had utilized plant protein sources as opposed to whey protein isolates in order to produce a broader spectrum of health benefits and help avoid some unnecessary side effects.

Rule One Protein review conclusion: Is Rule 1 whey protein good?

Bottom Line: All things considered in our Rule One Protein review, we believe Rule 1 Protein is not worth it based on our analysis of the Supplement Facts Panel and whey protein blend. The supplement facts panel is actually very clean nutritionally speaking. The problem lies within the whey protein blend. As I spoke about before, I simply don’t feel comfortable recommending whey protein products to my clients based on how much more effective and efficient plant-based protein powders are.

Here is my review of the protein powder that I personally use for those interested: VegaTein Review.

Rule 1 review FAQs

Does Rule 1 Protein make you gain weight?

R1 Protein can help you gain lean muscle if you use it properly, but it will not cause you to gain fat since it does not contain any fat, sugar, or carbs. The bottom line is it can only help you gain the good type of weight, meaning muscle. That’s not to say it can help with weight loss, though. Protein powders generally can not help induce weight loss.

Is Rule 1 Protein lactose free?

No, R1 Protein is not lactose free because it uses whey protein isolate and hydrolysate, which contain milk and soy. This is very unfortunate because lactose free protein powders are generally much more effective, as I talked about earlier. Lactose causes a ton of health problems, specifically in your digestive tract and gut, which is why I recommend avoiding protein powders that contain lactose.

Is Rule 1 Protein gluten free?

R1 Protein is gluten free because all forms of whey protein are gluten free, and the protein sources it contains are strictly whey protein sources. Zero gluten is a huge bonus for a protein powder that already has an elite nutrition panel, but you can’t forget about the fact that it contains lactose, dairy, soy, and other ingredients that ultimately make the fact that it is gluten free irrelevant.

Is Rule 1 Protein dairy free?

Whey protein isolate by nature can not be free of dairy or lactose because the forms of protein it uses are whey proteins. Whey proteins are derived from milk. Therefore, the product is naturally going to contain dairy and lactose, both of which are very bad for your gastrointestinal health. This is why I strongly urge my clients and readers to stick with plant-based protein powders, which are dairy free and lactose free.

Is Rule 1 Protein safe during pregnancy?

I’m a certified nutrition and wellness consultant, but I am not a doctor. Therefore, I’m not qualified to answer this question. I would strongly recommend consulting your doctor with this question before trying R1 protein.

Where to buy Rule 1 Protein at the best price

First of all, how much does Rule 1 Protein cost? Let’s take a look at where to buy Rule 1 Protein & get the cheapest deal on prices:



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Certified Nutrition Coach at JNC Enterprises Inc. | Website | + posts

I’m not just a supplement analyst. I’m an extremely qualified one! I am a Certified Nutrition Coach (CNC) and actually received my certification directly from the National Academy of Sports Medicine. I am also a Nutrition & Wellness Consultant, certified by the American Fitness Professionals Association (AFPA).

Hi, I’m Joe Costello CNC

I’m not just a supplement analyst. I’m an extremely qualified one! I am a Certified Nutrition Coach (CNC) and actually received my certification directly from the National Academy of Sports Medicine. I am also a Nutrition & Wellness Consultant, certified by the American Fitness Professionals Association (AFPA).