Isopure vs Transparent Labs

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This is a detailed comparison of two leading protein powders: Transparent Labs Whey Isolate and Isopure Whey. I used both proteins for over a month and documented everything I liked and didn’t like about each to write the most unbiased guide and help you decide which product to get. 

See our Transparent Labs review here and our Isopure review here.

Both reviews are pretty detailed, but they don’t exactly tell you how the two proteins compare, so let’s put them side by side in the eight major categories:

• Ingredients
• Quality Assurances
• Protein Percent of Calories
• Taste
• Mixability
• Texture
• Satiety
• Cost

No Time to Read? Here’s The Winner:

After comparing the two proteins side by side, Transparent Labs Whey Isolate won. That said, Isopure offers some unique benefits and might be worth it for some people, so keep reading to learn more.

Note: For brevity, I’ll refer to transparent Labs Whey Isolate as ‘TL whey isolate.’

Key Takeaways

• TL whey isolate is a grass-fed product with no artificial ingredients. It has 84-86% protein, and each scoop offers around 28 grams. Isopure is also an isolate but has some artificial additives. It is claimed to have 91-100% protein, but that isn’t verified since they don’t do third-party testing.

• TL whey isolate is an excellent product for people who want a natural protein powder that relies on ingredients like salt, stevia, cocoa powder, and evaporated cane juice sugar for its taste and texture. In contrast, Isopure might be better for people who want a higher percentage of protein per serving and some extra vitamins and minerals.

• Both products come from respectable and established brands that have combined decades on the market. However, with its clean-label approach, quality assurance, extra flavor options, and more reliable and consistent cost per serving, Transparent Labs is ideal for people who want to get a better bang for the buck.

What Is Transparent Labs Whey Isolate?

Transparent Labs is a supplement company that prides itself on its openness and transparency with its user base. Unlike many companies that hide their ingredients behind proprietary blends, TL lists them openly and tests each batch to ensure purity and quality.

You can access previous results on their third-party testing page. Search for the lot number on your product’s tub or bag and click on the result to see the findings. (Sometimes, newer test results might not be uploaded, so email them if you can’t find yours. They respond within two to three days.)

Now, onto the protein at hand. This is a whey isolate, which means it’s more refined and has small amounts of carbs and fats. Around 84-86% of its calories come from protein. For reference, a 34-gram scoop (one serving) provides roughly 28 grams of protein.

Certain flavors like Chocolate Peanut Butter may have slightly less protein––around 28 grams per 37-gram scoop. This means the protein as a percentage of calories can be around 75%, so double-check your preferred flavor’s nutritional information to avoid surprises later.

But despite some flavors having slightly less protein, this is still well above other powders we’ve tested. For example, Pure Protein and MuscleTech have 60% and 57% protein, respectively.

Also, ‘grass-fed’ means this whey protein comes from cows primarily fed a grass-based diet, which is considered healthier than the typical cow diet consisting of grains, silage, and various non-organic supplements. 

Another advantage of TL whey isolate is that it only has a handful of natural ingredients like stevia, salt, cocoa powder, and evaporated cane juice sugar.

The only real drawback is that its price per serving is $2.00, well above the average of $1.34 (based on our calculations for 30+ protein powders). But given the brand’s transparency, clean label approach, high protein quality (and protein as a percent of calories), consistent testing of the purity, and multiple flavors to pick from, this cost is justified. 

Pros

• Around 28 grams of protein per scoop (can vary a bit based on the flavor)
• 100% grass-fed whey protein
• Consistent and reliable third-party testing to ensure purity and quality
• Simple ingredient list with no artificial additives
• Multiple flavor options, a rich taste, and good mixability

Cons

• The cost per serving is well above the $1.34 average

Who Should Take It?

TL whey isolate is perfect for:

• Gym-goers and athletes looking to boost their protein intake

• People who are okay with paying a bit extra for quality and ensured purity

• Those who prefer grass-fed whey protein

• People with lactose sensitivity (given the higher protein, TL whey isolate has less milk sugar and might be more tolerable than other whey proteins)

What is Isopure Whey Isolate Protein?

Isopure is a company that advertises its protein as zero/low-carb. This might not seem like a unique value proposition today, but it was certainly novel when their protein powder launched in 1998. 

At that time, there were significantly fewer protein isolates and products low in sugar. Since those early days, Isopure has stayed mostly committed to one category: protein powders. 

So, what can we say about Isopure today? As a company, Isopure has continued to be one of the big brands. One likely reason is that they’ve stayed focused on creating one quality product instead of trying to occupy as much shelf space as possible by branching out into a thousand mediocre directions.

Today, Isopure offers multiple types of protein powders: their zero/low-carb whey isolate (more on it in a moment), a collagen protein, a vegan product, pre-mixed protein drinks, and Infusions, a high-protein beverage with fruit flavors. Also a few newer products like creatine and colostrum.

Isopure Whey Isolate is protein powder with 20+ added vitamins and minerals. You can get it unflavored or in several flavored forms. The macronutrient profile per scoop is as follows:

• 25 grams of protein
• 1 gram of carbs
• 0.5 grams of fat
• 0 grams of sugar

Depending on the flavor, the product has 100 to 110 calories per scoop, which means its protein as a percentage of calories is between 91 and 100%. The flavors with 100% protein are vanilla salted caramel, strawberries and cream, creamy vanilla, banana cream, and toasted coconut.

That said, while 100% protein per serving sounds alluring, don’t take out your wallet yet. It sounds good, but Isopure doesn’t allow third-party testing to confirm their claims. Until they do, I will take their claims with a grain of salt.

For example, while TL whey isolate might offer less protein than what Isopure claims, each batch is third-party tested, and you can find the lab analysis for your personal product. 

Pros

• Added vitamins and minerals for a nutritional boost
• It tastes and mixes great
• The brand has been around for a long time, so they must be doing something right
• The listed protein as a percent of calories is unbeaten

Cons

• The product is not third-party tested
• The cost per serving ranges from $1.58 to $2.28

Who Should Take It?

Isopure protein is excellent for:

• People looking to boost their protein and overall nutrient intake

• Those who want a zero or low-calorie product with a lot of protein per scoop

• People on a keto diet (since there’s virtually no carbs)

• Those who don’t mind paying a bit more and don’t care for third-party testing

Main Differences: Transparent Labs Whey Isolate vs Isopure

Ingredients

The Winner: Transparent Labs

While Isopure may look better on paper, the company uses artificial flavoring agents to improve its powder’s taste. Additionally, some flavors contain artificial coloring agents, which may be linked to some adverse health effects. 

On the other hand, TL whey isolate is a clean-label product that contains only natural ingredients. It’s made with grass-fed whey and has a handful of ingredients: stevia, salt, evaporated cane juice sugar, and cocoa powder. 

So, while neither product has a mile-long ingredient list, Transparent Labs wins this category.

Quality Assurances

The Winner: Transparent Labs

Isopure is a fantastic product on paper. However, one significant drawback is that the company doesn’t do any third-party testing, making it impossible to verify their claims. 

For instance, the company claims that a handful of its flavors are 100% protein, which is suspicious given that even the best brands rarely exceed 85-90%. Even their ‘lower’ protein flavors are 91+%, which is far above the average. 

This isn’t to say that Isopure is being dishonest. But given that third-party testing is becoming increasingly common, we aren’t sure why they wouldn’t subject their proteins to it to boost their credibility.

In contrast, Transparent Labs lists everything on its nutritional labels, tests every batch of its products, and publishes the lab analyses on its website. So, Transparent Labs is the clear winner here.

Protein Percent of Calories

The Winner: Isopure

As discussed, Isopure’s whey protein isolate offers 91-100% protein as a percentage of the total calories, which no other product can beat. 

In contrast, TL whey isolate offers 84-86% protein, which is still impressive but not enough to win this category.

Taste/Flavor

The Winner: Transparent Labs

TL whey isolate has 10 flavor options, including the classics like vanilla and chocolate, as well as less common options like blueberry pancakes and oatmeal chocolate chip. 

The taste was milder than other proteins but still sweet, and I could tell the difference. My top two picks were Mocha Latte and Dark Chocolate. 

Isopure offers three flavoring options: unflavored, Dutch Chocolate, and Vanilla. I enjoyed the Dutch Chocolate and can see how some people might prefer an unflavored whey protein.

However, despite offering an unflavored option (TL doesn’t have one), Transparent Labs wins this category because it has many flavor options, and the ones I’ve tested are fantastic.

Mixability

The Winner: Tied

Neither product was inherently better or worse than the other. I had no issues mixing a scoop of Isopure or Transparent Labs whey isolate with water or milk. 

Both proteins mixed incredibly easily when added to a shaker, and it wasn’t hard to get a smooth and creamy mixture when I used a spoon or fork to stir them in a glass.

Texture (Thick or Thin)

The Winner: Tied

Whey isolates proteins typically have a thin mixture, especially when added to water. However, I found both of these products to be on the thicker side, so I can’t say that either is better than the other.

Satiety

The Winner: Tied

This is the third category in a row where I couldn’t define a clear winner. Whey isolate is more refined and easier to digest, which means it doesn’t sit in your stomach as long as less refined products like whey concentrate. 

Because of that, you can’t expect either product to keep you full that long. To test their satiety, I mixed each powder with five ounces of 2% milk and had each shake at 8 AM. I started feeling hungry at roughly the same time.

Cost

The Winner: Transparent Labs

Transparent Labs (TL) Whey Isolate costs $2.00 per serving, which is higher than the $1.34 average per serving across 30+ protein powders we’ve reviewed at FeastGood.com.

Isopure’s price ranges from $1.58 to $2.28 per serving, meaning it can be cheaper than TL, but that’s not guaranteed—you might end up paying more than $2.00 per serving.

Given Transparent Labs’ stable and predictable pricing, it offers better cost certainty, making it the winner in this category.

Where To Buy

Transparent Labs Whey Protein

Transparent Labs Grass-Fed Whey Isolate is the #1 protein recommended by FeastGood.com.

Isopure Protein

With its straightforward ingredient list, high protein percentage, good taste, texture, and mixability, and satiety score similar to TL whey isolate, Isopure is a good alternative.

What Other Experts Are Saying

• Hafþór Júlíus Björnsson (The Mountain from Game of Thrones) has been a Transparent Labs athlete since 2020. Aside from his impressive acting credits, he won the World’s Strongest Man, Europe’s Strongest Man, and Arnold Strongman Classic competitions.
  
  He endorses TL products and often posts about using them daily to support his training and recovery.
  
  For instance, here’s a video of his wife, Kelsey Henson, preparing his favorite pancake recipe with TL whey isolate.
  
  In 2023, The Mountain completed an impressive weight loss transformation and credited Transparent Labs Whey Isolate as a significant part of his journey.

• Brianna Bernard, a personal trainer, nutrition coach, and competitive powerlifter, is an Isopure athlete. She gained 70 pounds during her pregnancy in 2012 and successfully lost 100 lbs in the next few years.
  
  Since then, she’s been helping people sustainably lose weight and lead healthier lives.
  
  Brianna emphasizes the importance of eating enough protein and often shares simple recipes featuring Isopure whey. For instance, she shares a quick and easy protein yogurt parfait with Isopure whey here.