RSP TrueFit Lean Protein Shake Review — No Iron or Zinc?

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Based in Miami Beach, RSP is a supplement company that was founded by former student athletes and while RSP used to focus more on bodybuilding, they’re a little more general in their approach now, stating that they want RSP to become a “lifestyle brand that our customers embody in their everyday lives.”

We’ve tried their amino acid powder, but TrueFit is their flagship product: a protein shake that they claim “offers the ideal balance of high quality protein, fruits and vegetables, dietary fiber, 9 grams of low-glycemic carbs, and healthy fats.”

Let’s take a look at the Gourmet Chocolate Milkshake flavor.

RSP TrueFit Lean Protein Shake
RSP TrueFit Lean Protein Shake
Well priced and high in nutrients, RSP has an unusually strong emphasis on digestive health: lots of fiber, lots of probiotics, and lots of enzymes make for a very well rounded and tasty shake.MoreLess

RSP TrueFit Lean Protein Shake Nutrition

One scoop has 160 calories: 25 grams of protein, 12 grams of carbs (8 grams of fiber, 2 grams of sugar) and 3 grams of fat (2 grams saturated fat). One scoop has 20 percent of your daily cholesterol and 9 percent of your daily sodium.

As far as vitamins and minerals go, there’s roughly 30 percent of the recommended daily intake of a pretty wide variety of nutrients: Vitamins A, C, D, E, B-vitamins, biotin, and magnesium.

RSP TrueFit Lean Meal Replacement Ingredients

RSP TrueFit Lean Protein Shake Ingredients

The protein comes from whey concentrate and isolate, and the flavorings come from cocoa, natural flavors, stevia, and the artificial sweeteners sucralose and acesulfame potassium. There are no artificial colors, flavors, or preservatives, but there are artificial sweeteners, albeit less than 0.1 grams per serving.

The fiber comes from 8.5 grams of prebiotic soluble fiber (from a company called VitaFiber) and sweet potato powder. There’s also 1 gram of an All-in-One Superfood Blend of a variety of fruits and vegetables: broccoli sprouts, berries, tomato, carrots, and so on.

Finally, there are ingredients geared toward digestive health: seven digestive enzymes (amylase, papain, bromelain, lipase, protease, lactase, cellulase) and 1 billion probiotic bacteria from lactobacillus acidophilus.

[TrueFit made our list of the best meal replacement shakes! Click through to learn why.]

RSP TrueFit Lean Meal Replacement Review

RSP TrueFit Lean Protein Shake Benefits and Effectiveness

For starters, it’s encouraging that the product has such a focus on digestion. The probiotics, prebiotic fiber, and the digestive enzymes may improve gut health and nutrient absorption, and they can be particularly useful for folks who have trouble digesting the lactose in whey concentrate.

This is also remarkably high in fiber: 8 grams of fiber for 12 grams of carbohydrates. That also means it’s very low in net carbohydrates, which coupled with its low fat content (3 grams per serving) means it isn’t a great meal replacement, it’s more of a very nutritious protein shake.

So what about the nutrition? RSP claims that with one scoop “you’ll get everything you need, a clean, balanced, and filling shake to support your fitness goals.” This isn’t quite true. While it’s far more nutritious than your average protein shake, it’s missing a few nutrients.

A lot of meal replacements leave out lesser known nutrients like Vitamin K and choline. RSP is one of them, but there are a lot of other holes in the nutrition profile: there’s next to no potassium, it’s pretty low in calcium (13% of the RDI), and there’s no iron or zinc. These are pretty important nutrients and it’s unusual to see a product like this skimp on them.

RSP TrueFit Lean Protein Shake Price

For a two-pound tub, you’re looking at paying 25 to 30 dollars for 20 servings, or around $1.40 per serving. That’s pretty reasonably priced for a meal replacement.

RSP TrueFit Lean Protein Shake Taste

The Gourmet Chocolate Milkshake flavor tasted like a diet brownie or a not-particularly-moist chocolate cake. I wouldn’t call it Gourmet, but it was perfectly passable.

The Takeaway

RSP has done a pretty good job of producing a nutritious, high fiber protein shake with a focus on digestive health. I had a few things I didn’t love: it’s too low in carbs, fat, iron, zinc, and potassium to really replace a meal. But it’s certainly a step up from your usual protein shakes.

RSP Nutrition TrueFit

Per Serving: $1.40










  • Reasonably priced
  • High in fiber
  • May have digestive benefits


  • Low in carbs and fat
  • Low or no iron, potassium, calcium, zinc
  • Has soy and artificial sweeteners
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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