Many people have seen and tried protein supplements containing whey, but whey isolate is taking the sports nutrition world by storm as it’s a highly digestible protein source. (1) We love Isopure Zero Carb Whey Protein since it’s one of the best protein powders for those seeking a lean whey isolate supplement that mixes well, helps supplement vitamins and minerals, and is reasonably priced.
Our team of fitness experts and registered dietitians personally used over 100 protein powders using our supplement testing methodology and against criteria including its ingredients and formulation, third-party testing status, price per serving, taste and flavor, and solubility. Isopure was one of the products we extensively tested to bring you detailed reporting so that you can decide whether it’s a good fit for your needs. Learn more in our Isopure Protein review below.
Editor’s note: The content on BarBend is meant to be informative in nature, but it should not be taken as medical advice. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. It’s always a good idea to talk to your doctor before beginning a new fitness, nutritional, and/or supplement routine. Individual needs for vitamins and minerals will vary.
Isopure Zero Carb Protein Powder provides a whopping 25g grams of protein with zero carbs and zero fat per 100 calories scoop. This zero carb protein supplement is also packed with vitamins and minerals that can help support your keto diet, and fill micronutrient gaps.
Main Takeaways
- 25 grams of high-quality whey isolate with a vitamin and mineral blend and low in fat and carb macros, making it ideal for those looking for a leaner protein choice
- Excellent solubility, so you don’t end up with a clumpy mess
- Not the strongest when it comes to taste or clean ingredients, but it’s gluten-free, lactose-free, and good value for your money compared to other whey isolates
Isopure Protein Powder Specs
| Price Per Serving | $1.47 to $2.13 |
| Protein Per Serving | 25 grams |
| Calories Per Serving | 100 to 110 calories |
| Sweeteners Used | Sucralose |
| Available Flavors | Banana Cream, Chocolate Peanut Butter, Cookies & Cream, Creamy Vanilla, Dutch Chocolate, Strawberries & Cream, Vanilla Salted Caramel |
| Third-Party Testing | No |
Isopure Protein Powder is an excellent choice for those who need protein with fewer other macros. With 25 grams of whey isolate and starting at only 100 calories per serving, it’s a great protein supplement for athletes seeking a leaner protein powder. It’s not the cleanest option since it does contain fillers and artificial ingredients, but it’s fairly priced for a whey isolate, which often costs more than standard whey options.
Isopure offers its whey protein isolate products in seven different flavors. What it lacks in taste, it makes up for in its excellent solubility. Say goodbye to clumpy powders that leave residue at the bottom and sides of your shaker bottle with Isopure. It also contains a vitamin and mineral blend, which can help supplement your needs if you don’t meet them from food alone.
While this product is free from gluten and lactose, it is not plant-based, since the whey comes from cow’s milk. So, if you prefer vegan or vegetarian-friendly options, you may want to consider some of the best vegan protein powders or best hemp protein powders.
Read on for our full Isopure Protein Powder Zero Carb review.
Who Should Use / Who Shouldn’t Use Isopure Protein Powder
While protein powder benefits are well-known, choosing the right product is critical to ensuring it aligns with your goals, dietary needs, and preferences. If you’re considering Isopure as your protein supplement, read our recommendation for who should and shouldn’t use this product.
Recommended for:
- High protein diets, weight loss
- Those who prioritize mixability
- Those allergic to or limiting gluten and lactose
Not Recommended for:
- Keto diet, weight gain, bulking
- Those who are picky about taste
- Natural product enthusiasts
Our Experience Using Isopure Protein Powder
Isopure Protein Powder is one of the best whey protein powders our team has tried. It consists of 25 grams of whey isolate, which contains essential amino acids to support muscle growth and recovery and is a highly digestible protein source. (1)(2)(3)
Athletes who are considering Isopure Protein Powder will enjoy its excellent solubility and vitamin and mineral content. It’s also free from gluten and lactose for those with dietary restrictions. However, Isopure is high in sodium, so it’ll taste slightly salty and not as sweet as other protein powders. It’s also not third-party tested, although the brand has a strong reputation. We also thought it was a fair price for what you get.
This section details the nitty-gritty from our team of fitness experts and registered dietitians who have tried Isopure Protein Powder first-hand.
Ingredients and Formulation
Based on the Isopure Protein Powder ingredients, it scores a 4.25 out of 5 for its formulation, with deductions for its high sodium content, inclusion of fillers and artificial ingredients, and its low carb and fat content. Adding Isopure to your diet is an easy and convenient way to increase your protein intake. Whey protein isolate is a highly digestible, pure protein source compared to standard whey because of the way that it’s processed – it’s lower in lactose content and higher in protein content. (1)
Plus, 25 grams of protein is enough to support most athletes in meeting their higher protein needs and support muscle-building post-workout. While sedentary individuals only need about 0.8 grams of protein per kilogram of body weight per day, many athletes need up to 1.6 grams per kilogram of body weight per day. (4)(5) Given the higher protein content, this powder can help athletes support their weight cuts or limit their fat and carb macros, making it one of the best protein shakes for weight loss.
Chelsea Rae Bourgeois, M.S., R.D.N., L.D., who is a registered dietitian, states, “I like that Isopure Zero Carb Protein found a way to pack in 25 grams of protein without adding carbs and fat. This protein powder is great for those who need to increase their protein intake without skewing their other macros.”
We also loved that this product contains a vitamin and mineral blend containing calcium, potassium, vitamin A, vitamin C, vitamin E, vitamin K, thiamin, riboflavin, niacin, vitamin B12, biotin, folate, vitamin B6, biotin, pantothenic acid, phosphorus, iodine, magnesium, zinc, selenium, copper, manganese, chromium, molybdenum, and chloride. While you should aim to meet your micronutrient needs from food, this powder can help supplement what you don’t get.
However, the formulation could use some areas of improvement. Its ingredient list contains fillers like soy lecithin and xanthan gum that don’t contribute any nutritional value, as well as artificial ingredients like sucralose, which many people choose to avoid. Moreover, it’s high in sodium compared to USDA recommendations – each scoop contains 240 milligrams of sodium which is a little over 10 percent of the recommended sodium intake. For context, the USDA recommends limiting sodium intake to less than 2300 milligrams per day. (4)
While the high protein content is ideal for those looking to increase their protein intake, the carbohydrate (up to 1 gram, depending on flavor) and fat (0.5 grams) content might be too low for those who want to bulk, use their protein shakes as meal replacements, or follow a ketogenic diet. Those looking for higher macros may need to consider the best protein powders for weight gain instead.
Taste
Isopure Low Carb Protein Powder only scored 2 out of 5 for its taste. Isopure Protein drink reviews on the manufacturer’s website and on Amazon state that there’s a tinge of saltiness and bitterness to it.
Our tester, who is a certified nutrition coach, states, “I experienced some unpleasant saltiness in the mixture, and there wasn’t much flavor going on with this powder, even when added to milk. If you want a sweet, scrumptious protein powder, I’d recommend opting for a different formulation.” We liked the Dutch Chocolate flavor the most out of the tested flavors.
According to Bourgeois, this product’s ingredients and macros are to blame for its not-so-sweet taste. Bourgeois states, “Without carbs and fat, this protein powder will have a very specific taste. It also contains artificial flavors and sweeteners, affecting the taste and overall experience.”
With many other protein supplement options offering delicious and decadent flavors, we’d recommend using this product for smoothies or milkshakes, where you can add other ingredients to mask its not-so-great taste.
Of course, if you prefer options that aren’t overpoweringly sweet, Isopure might be a good choice. Older athletes might like the milder taste of this product, or may want to check out our list of the best protein powders for seniors. I like unflavored and neutral-tasting protein powders like this, but I think most athletes I’ve worked with enjoy sweeter protein powders.
Solubility
After testing it in an electric blender and shaker bottle, we were impressed with Isopure Zero Carb Protein Powder’s solubility. Our tester gave it a score of 5 out of 5 and states, “I found this powder to be very mixable. There’s a bit of froth at the top when mixing this with a countertop blender, but I didn’t have a grainy texture when taking sips. There also wasn’t any residue at the bottom of my bottle or sticky substances along the sidewall.”
Some powders also clump over time while you’re on the go or during your workout, but that wasn’t an issue with Isopure. “You could easily set this down and sip it over a longer period without worrying about its consistency and texture,” our tester adds.
Price Per Serving
Out of the different types of protein, whey protein isolates typically cost a little more than standard whey powders, given their greater digestibility. The cost per serving starts at $1.47 for a bulk 7.5-lb tub (110 servings) if you know what flavor you’d like to get. Before buying in bulk, you may wonder, “Does protein powder expire?” And the good news is that whey isolate can last anywhere from eight to 15 months. (6) However, the cost per serving can be as high as $2.13 for a 1-lb, 15-serving tub.
If you’re comparing different protein powders, make sure you check the cost per serving rather than the cost per scoop. Depending on the protein powder, the serving size may be one scoop or two scoops, so calculating the cost per serving based on scoops may not be a good comparison. Other whey isolates can cost anywhere from $1.33 to $5 per serving, so we think Isopure is pretty competitive as far as cost goes.
Third-Party Testing
While Isopure has a long-standing reputation for delivering high-quality sports nutrition products, its Zero Carb Protein Powder is not third-party tested. Third-party testing helps ensure that the product is what the manufacturer states and helps us better judge the product’s quality, purity, efficacy, and accuracy of ingredients.
However, since protein powders are sold as food, rest assured that the FDA has a closer eye on products and their claims than supplements, which aren’t regulated. This means Isopure’s nutrition facts and ingredients were assessed before being sold online or in-store.
What to Consider Before Buying Isopure Protein Powder
Are protein shakes good for you? It depends on your dietary needs and preferences, but a suitable protein supplement can help you gain muscle and support recovery. (2) Here are some considerations before committing to Isopure Protein Powder.
- Macronutrient Needs: With 25 grams of protein per serving, Isopure Protein Powder is an excellent choice for those who need extra protein. However, it’s lower in fat and carbs if you need a better macronutrient balance.
- Protein Source: Before buying any protein powder, determine what protein source meets your needs and preferences. Isopure consists of whey isolate, which is a high-quality protein source that digests well. (1) Pro Tip: Casein is also a slowly digesting protein for your nighttime protein needs if you want to check out the best casein protein.
- Natural Ingredients: While some of the best organic protein powders boast clean and natural ingredients, Isopure contains fillers, artificial ingredients, and a vitamin and mineral blend – all of which some choose to avoid.
- Taste and Flavor: Isopure comes in seven different flavors but isn’t rated highly on taste. If you prefer a variety of flavors and a powder that tastes delicious, this product may not be the right fit for you.
- Mixability: While other protein powders can often be clumpy or leave residue at the bottom of the shaker bottle, Isopure mixes very well to provide a creamy and rich consistency in various liquids.
- Value: Whey isolates can cost anywhere from $1.33 to $5 per serving, so Isopure is priced competitively for what you get.
Isopure Protein Powder Vs. Competitors
With so many whey protein isolate products, from Isopure and Dymatize to Optimum Nutrition and Transparent Labs, it can take time to decide which one to choose. Read on to see a full comparison between Isopure Protein Powder and other leading whey isolate isolates.
| Isopure Zero/Low Carb Protein Powder | Transparent Labs Whey Protein Isolate | Momentous Whey Protein Isolate | |
| Price Per Serving | $1.47 to $2.13 | $2.00 | $2.43 to $2.70 |
| Protein Per Serving | 25 grams | 28 grams | 20 grams |
| Calories Per Serving | 100 to 110 calories | 130 to 140 calories | 90 to 100 calories |
| Sweeteners Used | Sucralose | Stevia Extract | Stevia (Organic Glycosylated Steviol Glycosides and Organic Rebaudioside A) |
| Available Flavors | Banana Cream, Chocolate Peanut Butter, Cookies & Cream, Creamy Vanilla, Dutch Chocolate, Strawberries & Cream, Vanilla Salted Caramel | Milk Chocolate, French Vanilla, Chocolate Peanut Butter, Dark Chocolate, Unflavored, Strawberry Milkshake, Cinnamon French Toast, Mocha, Vanilla Peanut Butter, Mint Chocolate Chip, Blueberry Pancakes, Peanut Butter, Vanilla Oatmeal Cookie, Sugar Cookie, Oatmeal Chocolate Chip Cookie | Chocolate, Vanilla, Unflavored |
| Third-Party Testing | No | Informed Choice, Informed Protein, Various Laboratories | NSF Informed Sport |
These products were selected alongside Isopure for comparison since they’re all well-regarded in the sports nutrition industry and are popular whey isolates athletes use. They all offer unique benefits that may be of varying importance depending on your needs.
While Isopure is excellent for counting macros and strictly monitoring carb or fat intake, vitamins, and minerals, it contains artificial sweeteners. It is also less highly rated on taste. Transparent Labs boasts the cleanest label, with whey protein derived from grass-fed cows. It offers many flavors rated highly for taste, has no artificial ingredients, and is third-party tested.
Momentous Whey also offers whey isolate from grass-fed cows like Transparent Labs but has stricter third-party testing and an NSF Informed-Sport Certification. Momentous Whey also claims to have collaborated with RDs and human performance specialists from professional sports teams when developing the formulation, but flavors are limited, and the chocolate and vanilla varieties contain low-grade fillers.
Places to Buy Isopure Protein Powder
If you prefer to shop online, you can buy Isopure Protein Powder on the Isopure website or on Amazon. Isopure offers free shipping on orders over $75 and often has promotions or bundle offers, while Amazon Prime members get free shipping and discounts for signing up for subscriptions. It’s also available on iHerb, which stocks many health supplements.
Or, if you prefer to shop in person, head over to a vitamin specialty store like GNC or The Vitamin Shoppe and look for the zero-carb variety. These stores often have a strong loyalty program to get Isopure Protein Powder at a discount and may even offer sample packs to try different flavors.
Customer Experience and Brand Reputation
The Isopure Company was introduced in 1998 by Hal and Ernie, who wanted a simple and clean protein product. Since then, the company has grown but still stands by its commitment to simplicity, purity, and quality, using 100 percent whey protein isolate in all its formulas. It has a positive reputation among athletes and everyday wellness enthusiasts alike. Many Isopure protein drink reviews cite its effectiveness for training.
For standard shipping, The Isopure Company offers delivery within three to eight business days — this is the default option that you get for free when you buy $75 worth of Isopure products. Next-day delivery costs $16.99 for delivery within one business day.
If you’re not 100 percent satisfied with Isopure Protein Powder, you can return it within 30 days of your purchase and provide your purchase order number. To get full credit, at least 75 percent or more of the product must be unused. So, go ahead and give Isopure a try, knowing that the company has your back if you don’t love it.
Our Final Verdict on Isopure Protein Powder
Isopure Protein Powder is an excellent option for a lean, high-protein supplement with minimal calories and carbs. While the ingredient list and taste might only satisfy some, Isopure offers whey isolate at a good value. We recommend trying a smaller tub or a sample pack before committing to bulk.
Isopure Protein Powder FAQs
Is Isopure protein powder good for you?
While what foods are considered good for you is highly subjective, Isopure Protein Powder consists of a high-quality source of protein dosed in appropriate amounts to support athletes in reaching their fitness, nutrition, and body composition goals. It also contains a vitamin and mineral blend and is low in fat and carbs, which many athletes find desirable and “good” for their diet.
Is Isopure a clean protein powder?
Isopure consists of whey protein isolate, which is an excellent and clean source of protein. It’s also gluten-free and lactose-free. However, if choosing a clean protein powder is a priority, there are cleaner protein powders out there since Isopure does contain artificial ingredients (like sucralose, an artificial sweetener) and some fillers.
Is Isopure protein vegetarian?
The whey protein in Isopure comes from cow’s milk, so it could be suitable for lacto-vegetarians and lacto-ovo-vegetarians. For stricter vegetarian diets that avoid dairy and eggs, I’d recommend a pea or soy protein — something truly plant-based.
Does Isopure protein cause bloating?
Several factors cause bloating, but one of the common reasons is high lactose content. Isopure, since it consists of whey isolate, is lactose-free from its processing methods, compared to standard whey. Choosing a whey isolate like Isopure could help minimize bloating in individuals with lactose intolerance or milk allergy.
How much does Isopure protein powder cost?
Isopure protein powder costs $1.47 to $2.13 per serving. The cost is lower for a bulk 110-serving tub, while a 15-serving small tub can cost up to $2.13. If cost is important, consider buying in bulk once you find a flavor you like. If you’re comparing the costs of protein powders, check the cost per serving, not per scoop, since other powders can contain more than one scoop per serving.
References
- Foegeding, E. A., & Luck, P. J. (2002). Milk Proteins: Whey Protein Products. Encyclopedia of Dairy Sciences, 1957-1960.
- Hulmi, J. J., Lockwood, C. M., & Stout, J. R. (2010). Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein. Nutrition & Metabolism, 7(1), 1-11.
- Pearson, A. G., Hind, K., & Macnaughton, L.S. (2023). The impact of dietary protein supplementation on recovery from resistance exercise-induced muscle damage: A systematic review with meta-analysis. European Journal of Clinical Nutrition, 77(8), 767-783.
- U.S. Department of Agriculture and U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2020-2025. 9th Edition.
- Nunes, E. A., Colenso-Semple, L., McKellar, S. R., Yau, T., Ali, M. U., Fitzpatrick-Lewis, D., Sherifali, D., Gaudichon, C., Tomé, D., Atherton, P. J., Robles, M. C., Naranjo-Modad, S., Braun, M., Landi, F., & Phillips, S. M. (2022). Systematic review and meta-analysis of protein intake to support muscle mass and function in healthy adults. Journal of Cachexia, Sarcopenia and Muscle, 13(2), 795–810.
- Wright, B. J., Zevchak, S. E., Wright, J. M., & Drake, M. A. (2009). The impact of agglomeration and storage on flavor and flavor stability of whey protein concentrate 80% and whey protein isolate. Journal of Food Science, 74(1), S17–S29.
