Can Eating David Bars Help You Shed Fat and Build Muscle?

There’s a new buzzworthy protein bar in town: David bars. Founded by one of the RXBAR co-founders and with funding drawn from health world moguls such as Peter Attia (writer of Outlive: The Science And Art of Longevity, and who also acts as David’s head of science) and Andrew Huberman (of podcast fame for Huberman Lab), David welcomed a whopping $10 million in seed funding back in 2024 to make what they define as a protein bar in its “idealized” state, similar to that Michelangelo statue named after the brand.

So, why the hullabaloo? The bar itself has serious macros with 28 grams of protein, 150 calories, and zero grams of sugar. Nor does it hesitate to get straightforward about its intentions. “More protein and fewer calories allow you to gain more muscle and less body fat,” the website says. “That’s exactly what this protein bar does.” Flashy new business is all about creating “tools” for shedding pounds, and these bars are their initial product.

It’s a tall order for a small tavern. Ranging from $3.25 to $4.75 per shot, these protein bars deliver big. Here’s what the experts have to say.

What is in a David Protein bar?

Protein
You have to give David credit; the bars contain more protein than most, with 28 grams. Composed of milk protein isolate, collagen, whey protein concentrate, and egg white, David bars boast an ideal 1.0 protein digestibility-corrected amino acid score—in other words, they contain all 20 amino acids, says Le. Of these, 12 can be synthesized by the human body alone, but assistance is required in the form of the other eight, and running short on each of them leads to a nutrition deficiency, he explains. It’s a perk to be getting all 20 aminos, but this is to be expected from a bar that mixes multiple animal-based protein sources and isn’t unique to the brand.

Though the amount of protein is impressive, there are a couple of quick points to mention. Because David bars consist of animal protein, they wouldn’t be for individuals seeking a vegetarian alternative. They also have eggs and milk in them, so individuals with sensitivity or allergy to these foods, be aware.

Binding And Fat

A little bit of food science 101: when you’re creating a protein bar, you’re going to need some ingredients in there to help hold the rest of it together. Among a few others, David bars utilize maltitol, allulose, and glycerin to accomplish this, which might make your stomach do flips if you ate them in excess.

“Malitol is a sugar alcohol and I don’t typically suggest those because they’re going to give you tummy problems,” states Stephens. “Most of the people that I work with get stomach cramps and stomach aches if they eat too much of those in one day.” But, a bar or two shouldn’t send you overboard. “Four of these will probably cause gastrointestinal distress from the glycerin and the allulose, and that’s the case with many of these products with allulose and glycerin in them,” explains Le.

As for fat, one ingredient is particularly noteworthy to Le: something known as modified plant fat, or, more technically, esterified propoxylated glycerol (EPG). It’s a type of fat that your body can’t metabolize—which serves to lower the overall number of calories in the bar—that you don’t see in a lot of foods, say Le. This is partly because it’s costly, and may perhaps account for the bar’s higher price tag. Due to ingredients such as EPG however, David bars contain a greater proportion of calories from protein, which according to Michael Russo, MD, a surgeon at MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center, can be helpful in losing weight.

One of Stephens’ least favorite ingredients? Palm kernel oil. That’s because it contains saturated fat, which has been shown to have an impact on cholesterol and cardiovascular health, she explains. But the evidence is conflicting regarding how bad palm kernel oil is for you, according to a 2018 systematic review in PLOS One.

(No) Sugar

While David bars don’t have any sugar, they do have artificial sweeteners, which is mostly something to consider taste-wise. Depending on the bar, you’ll find a combination of stevia, sucralose, acesulfame potassium, cocoa powder, and/or monk fruit. These are all standard flavoring components, says Le. “You would probably see this pretty often in other protein bars and protein powders,” he says.

There’s a trade-off with artificial and man-made sweeteners, too, Stephens points out. Because they’re not natural sources, they may be more difficult for your body to digest, and they also could lead you to eat more, not less, calories of the bar. “Research indicates that individuals tend to eat more of these foods containing artificial sugars,” she says.

None of those ingredients are a big worry, however, Dr. Russo and Le assert. “Some individuals may be sensitive to certain of these artificial sweeteners, but they are not problematic by any means,” asserts Dr. Russo.

Added to the protein, binding, sources of non-digestable fats, and artificial sweeteners, David bars are definitely a highly processed product, which one might want to bear in mind. “This is clearly not a clean-label protein bar,” claims Le. If you want something with natural ingredients, this doesn’t have it.” (Some less processed, simpler options would be RXBARs, Kind bars, or Rise bars, which all contain fewer and more actual food ingredients, but any protein bar will have some degree of processing.) If you don’t care that it’s processed and are willing to accept a highly-engineered, low calorie bar, “This is pretty cool,” Le says. “Honestly, I kind of think it’s a cool product.”

Will a David bar assist you in gaining muscle and losing fat?

While David bars are not without their benefits, a bar is not going to instantly cause you to lose fat and gain muscle (regardless of what Cady Heron said to Regina George when she offered her a Kälteen bar in Mean Girls). Exercise, the other foods you consume, sleep, genetics, and so on matter more.

These bars are certainly protein-rich, and protein does come in handy for both weight loss and muscle gain. It takes more time to digest, meaning you’ll feel full longer, Dr. Russo explains. It’s also the building block of muscle (and women should take in approximately 1.2 to 1.5 grams per kilogram of body weight in order to build tissue, FYI). The bars also contain a decent ratio of more protein to less carbs, which is a good breakdown for weight loss as well, he says.

But, are David bars truly a “breakthrough” as the site suggests? “I wouldn’t call it revolutionary,” says Dr. Russo. “I would call it a higher quality protein bar based on the amount of protein that’s concentrated in a bar.”. It’s not necessarily going to cause you to lose more weight than some other comparable protein bar. Provided that you’re getting your protein through regular exercise and a healthy diet, I believe that you can have that weight loss diet with any number of brands.”

And don’t forget, protein bars, much like protein powders, are a supplement to actual food. “It’s an easy way to pack in protein,” says Stephens. If you can’t quite hit your protein targets for the day, particularly in the morning when it can work well for satiety to get some in, a protein bar will fill the gap. It’s always best to stick to unprocessed whole foods whether the aim is weight loss, muscle gain, or general health, says Stephens.