What Is EPG? The “Modified Plant Fat” in David Bars, Shakes and HallPass Candy, Explained

If you have read the back of a David Protein bar, the new David milkshake or one of the 70-calorie HallPass candies now at Walmart, you have seen the same four words in the ingredient list: “modified plant fat (EPG).” It is how a 150-calorie bar gets the texture of a much richer one, and it is the ingredient people go looking for when they type the three letters into a search bar with the word “reddit” after it. Here is what it is, where it came from, what FDA did and did not say about it, and what the only human studies measured — with the doses, since the doses are the whole story.

The moleculeA fat with spacers in it

EPG stands for esterified propoxylated glycerol. An ordinary fat is a triglyceride: a small glycerol backbone with three fatty-acid chains attached. EPG keeps the backbone and the fatty acids, but, as FDA’s first letter on it puts it, has “propylene glycol units inserted between the glycerol backbone and the fatty acid chains.” Those little spacers get in the way of lipase, the enzyme your small intestine uses to cut fat apart for absorption. Epogee, the company that makes it, describes the result this way: EPG “moves through your body much like dietary fiber — largely intact and without being absorbed,” supplying 0.7 calories per gram against the 9 of ordinary fat. That calorie figure is the company’s; none of the published study abstracts states one, and FDA’s letters say the agency did not evaluate labelling claims.

The idea is older than the brand. The original patent for “non-digestible fat substitutes of low-caloric value” was filed by ARCO Chemical in 1986 and granted in 1989. Its safety studies, authored by a researcher listed at Best Foods, then part of CPC International, were published as a set in 2014 and 2015. All three FDA notices were filed by a small Indianapolis company, Choco Finesse, which later became Epogee. David Protein bought Epogee in 2025; its parent, Medici Brands, announced a $250 million funding round on September 2, reportedly at a $2.25 billion valuation, and names Epogee among its holdings.

Where it isEvery product that lists it, so far

As of this week, EPG appears on the ingredient lists of the David bars (in a “fat system” alongside coconut or palm kernel oil), the David frozen-dessert pints, the David milkshakes launched September 8, and the HallPass peanut cups and chocolate pieces from the same parent company. No other consumer brand currently lists it. Not one of these products discloses how many grams of EPG it contains. The best anyone outside the company can do is read the total-fat line as a ceiling: 1.5 to 2 grams in a milkshake, 2 grams in a bar, 3.5 to 5 grams in a HallPass pack, where peanut butter and palm kernel oil share that total.

The FDA partThree letters, and what they actually say

EPG is not “FDA approved,” a phrase that turns up in search summaries. It went through the voluntary GRAS notification program, in which a company concludes an ingredient is generally recognised as safe, sends FDA its evidence, and receives a response. EPG has three: GRN 583 (2015, confectionery coatings and inclusions), GRN 640 (2016, up to 21% of finished baked goods, frozen dairy desserts, sauces, nut products and soft candy) and GRN 761 (2018, frying oil for french fries and doughnuts). Each ends the same way: the agency “has no questions at this time” about the company’s conclusion, while, in the 2015 letter’s words, it “has not, however, made its own determination.” The 2018 letter is blunter: “This letter is not an affirmation that EPG is GRAS.”

Epogee’s FAQ summarises the same letters as meaning “the FDA raised no concerns about EPG’s safety for its intended uses.” Both statements are describing one process from different ends, and the letters are the primary source. Two further details are worth knowing. The letters’ “intended uses” do not include drinks; under current law a company may reach its own GRAS conclusion for a new use without notifying FDA, so that is a gap in the public paperwork, not a sign of anything improper. And that law may change: on August 11, FDA proposed ending self-affirmed GRAS altogether (docket FDA-2025-N-3262, comments open until December 9). Under the proposal, uses already covered by a “no questions” letter would be exempt and any other use would need its own notice. It is a proposal; nothing changes until a final rule.

The studiesTwo human trials, one clear dose line

The main study, Davidson and Bechtel 2014, fed 139 healthy volunteers 10, 25 or 40 grams of EPG a day for eight weeks, baked into spreads, muffins, cookies and biscuits, against a margarine control. The gastrointestinal side effects it lists are exactly what you would predict from a fat the gut cannot take apart: “gas with discharge; diarrhea; oily spotting; oily evacuation; oily stool; liquid stool; soft stool.” They “were reported more frequently” at 25 and 40 grams, “the incidence and duration of these symptoms correlated directly with EPG dietary concentration,” and the authors concluded that 10 grams a day “was reasonably well tolerated.” A second, shorter study gave 16 men single days of 30 to 150 grams; bowel function changed in one of them, at the top dose.

The same eight-week trial found something less discussed than bathroom effects: lower blood levels of beta-carotene and vitamin K1 in the EPG groups, and a rise in PIVKA-II, a marker that goes up when vitamin K status falls. Vitamins A, E and D were not significantly affected. The authors’ explanation is that EPG acts as a lipid “sink” on its way through, carrying some fat-soluble compounds out with it. The animal studies in the same series show the same pattern (lower liver vitamin E, less consistently vitamins A and D) without toxicity, and genetic-toxicity tests were negative. Two caveats belong next to all of it. Every published EPG study, human and animal, has an author from the company that developed it; no independent human trial exists in PubMed. And both human studies ran for days or weeks, not years.

The precedentHow olestra is different

The obvious comparison is olestra, the Procter & Gamble fat substitute approved in 1996 for savoury snacks. Chemically it is a different molecule (a sucrose core carrying six to eight fatty acids) built on the same idea. Regulatorily, it took a different road: a formal food-additive petition and a codified regulation, which required the famous “may cause abdominal cramping and loose stools” label until FDA removed it in 2003, partly on the strength of a 1998 cinema study of 1,123 people in which 15.8% of olestra-chip eaters and 17.6% of regular-chip eaters reported a GI symptom. One requirement never went away: olestra foods must still add back vitamins A, D, E and K to compensate for the ones it carries out. None of the EPG letters carries an equivalent requirement, and none of the EPG products lists added fat-soluble vitamins.

The court filesTwo cases, neither about the gut

EPG comes up in two lawsuits, and neither turns on digestion. A January class action alleged David bars held far more calories and fat than labelled, based on standard lab methods that count all the energy in a food whether or not a body absorbs it; the complaint does not mention EPG by name, and on March 30 the plaintiffs withdrew it themselves, without prejudice. A separate antitrust case brought by smaller bar makers who say they lost access to EPG after David bought Epogee is still pending in federal court in New York, after an earlier version of the complaint was dismissed in February and a revised one filed in April.

The bottom lineWhat it means for one bar or one shake

Put the pieces together and EPG is well described: a fat engineered to pass through, whose predictable effects (oily, loose stool and gas with discharge) appeared in the published trial at 25 to 40 grams a day and not, to any notable degree, at 10. A single bar or shake cannot contain more than its 2 grams of total fat, far below that line, which is why, as we found reading the David milkshake, the fat is rarely the likeliest explanation when one of these products disagrees with someone. The sugar alcohols, rare sugars and added fibers sitting in the same products usually are — the subject of our read of the HallPass candy label. What nobody outside the company can calculate is a heavy day’s total across several EPG products, because no label gives the grams. For what an oily or floating stool means when it does show up, that has its own explainer. Epogee, David Protein and Medici Brands had no involvement in this article. It is educational, describes what the cited letters, studies and ingredient lists say, and is not medical advice.