Onnit’s Grass-Fed Whey Isolate Review — The Best Digesting Protein Powder?

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Onnit is one of the fitness industry’s biggest giants even though their approach to wellness is somewhat unconventional. On the equipment side they’re perhaps best known for focusing on kettlebells, clubs, and maces, and on the nutrition side their most famous products are nootropics like Alpha Brain and stimulant-free, plant-based pre-workouts.

Until recently, their best known protein was probably their hempseed powder and while they have sold a goat whey-based recovery drink for some time, their product line has been missing regular whey protein powder.

Until now. Here’s what we thought of the Mexican Chocolate flavor.

Onnit's Grass-Fed Whey Isolate
Onnit's Grass-Fed Whey Isolate
A grass-fed whey isolate that has more ingredients for digestive health than any other on the market.MoreLess

Onnit Grass-Fed Whey Isolate Nutrition Info

One scoop has 120 calories: 20 grams of protein, 5 grams of carbs (2 grams of fiber, no sugar) and 2 grams of fat (0.5 grams saturated). There’s no information about cholesterol content.

That’s more carbs and fat than you might expect for a whey isolate, which often contain under a gram each of carbs and fat.

Tthe only other things that are notable on the nutrition side is that it’s a little higher in sodium than some protein powders (157mg, or 7 percent of the recommended daily intake) and it’s low in calcium. There’s just two percent of the RDI of calcium, and most wheys fall between 5 and 15 percent.

Onnit Grass-Fed Whey Isolate Ingredients

The whey is sourced from free-roaming, grass-fed New Zealand dairy cows and it’s processed into whey isolate, which is lower in fat and carbs than the cheaper whey concentrate.

The other ingredients are cocoa, sunflower oil, maltodextrin (or tapioca), dried cream extract, medium chain triglyceride oil, natural flavors, sunflower lecithin, cinnamon, organic rice hull concentrate — that’s a natural anti-caking agent — and a remarkable blend of seven digestive enzymes (amylase, protease, lipase, cellulase, lactase, papain, and bromelain).

For flavoring, there’s also some salt, stevia leaf, and monk fruit extract.

The last ingredient on the list is one I’ve never seen in a whey protein before: lactobacillus acidophilus, a probiotic bacteria that’s often found in yogurt.

Onnit Grass Fed Whey Isolate Ingredients

Onnit Grass-Fed Whey Isolate Benefits & Effectiveness

Onnit’s brand tends to focus on natural ingredients, and their whey is no different: it has no artificial flavors or sweeteners (so it’s Paleo-friendly if you’re comfortable with dairy) and it’s made from free-roaming dairy cows. Since most of the beneficial fats are removed, the additional health benefit may be small, but some users might be glad to know that the dairy they’re consuming comes from cows that weren’t confined to feedlots.

Onnit Grass Fed Whey Isolate Review

I’m also not sure why it contains medium-chain triglyceride oil, a product that Onnit sells for its purported cognitive benefits — there’s so little fat in this product that there’s likely only small nutrition benefit. The reason it’s included could be for flavor, like the dried cream extract.

The most remarkable ingredients are the seven digestive enzymes and the probiotic bacteria. The idea is that these ingredients may help improve absorption of the protein, helping you get more nutrition and muscle out from each scoop. It can also help reduce digestive discomfort if protein powders tend to cause stomach troubles, and while the product is meant to be lactose- and sugar-free, the enzyme lactase may make things better for folks who tend to have issues digesting dairy.

We named Onnit’s the best all natural whey protein on the market. Click the link to see our full list!

Onnit Grass-Fed Whey Isolate Taste

The Mexican Chocolate flavor is great. Don’t expect a traditional chocolate flavor, though — this tastes like cocoa mixed with chai tea and it has a warming cinnamon flavor. With milk it was delicious and I was surprised to find that even with water it was pretty enjoyable, largely due to the cinnamon. With one cup of hot water, I’d venture that it would even make a good hot chocolate.

We also tried the Vanilla flavor (which has ten fewer calories per scoop) and it was fantastic: it’s more ice creamy than velvety, bordering on birthday cake flavor.


For a product with no soy lecithin, I was surprised by how well this product mixed. It didn’t take much shaking for the protein to completely disperse in milk and in water; there was no difference in mixability.

The Takeaway

If you like Onnit’s products, you will probably like their new whey isolate. If you’re comfortable with paying an above-average price and you don’t mind that it’s a little higher in carbs and fat than other isolates, this is a very impressive protein powder. That’s not just because it pulls off the feat of tasting delicious and creamy without artificial ingredients, but because of the unmatched commitment to improving digestion and absorption.

Onnit Grass-Fed Whey Isolate

Per Serving: $2.00












  • No artificial ingredients
  • Very high in digestive enzymes and probiotic bacteria
  • Sugar-free


  • Expensive
  • More carbs and fat than other whey isolates
  • A little high in sodium and low in calcium
Nick English

Nick English

Nick is a content producer and journalist with over seven years’ experience reporting on four continents. His first articles about health were on a cholera outbreak in rural Kenya while he was reporting for a French humanitarian organization. His next writing job was covering the nightlife scene in Shanghai. He’s written on a lot of things.

After Shanghai, he went on to produce a radio documentary about bodybuilding in Australia before finishing his Master’s degrees in Journalism and International Relations and heading to New York City. Here, he’s been writing on health full time for more than five years for outlets like BarBend, Men's Health, VICE, and Popular Science.

No fan of writing in the third person, Nick’s passion for health stems from an interest in self improvement: How do we reach our potential?

Questions like these took him through a lot of different areas of health and fitness like gymnastics, vegetarianism, kettlebell training, fasting, CrossFit, Paleo, and so on, until he realized (or decided) that strength training fit best with the ideas of continuous, measurable self improvement.

At BarBend his writing focuses a little more on nutrition and long-form content with a heaping dose of strength training. His underlying belief is in the middle path: you don’t have to count every calorie and complete every workout in order to benefit from a healthy lifestyle and a stronger body. Plus, big traps are cool.

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