Consumer health & wellness · Functional coffee
Rarebird
Coffee with the caffeine stripped out and paraxanthine, caffeine’s main human metabolite, infused back in. Three US patents, $1.76 million from the National Science Foundation, one company funded rat safety study, and a new name since September 2026.
Sixty milligrams of a molecule you already make
The bag looks like any other bag of specialty coffee: single origin Colombian arabica, roasted to order, ground. You brew it like anything else.
What is different is invisible. The beans went through a sugarcane ethyl acetate decaffeination step that pulled the caffeine out, then through what the company calls a reverse infusion that put something else in: 60 milligrams of paraxanthine per six gram serving.
Paraxanthine is not exotic. It is what your liver makes from caffeine, at 70 to 80 percent of an ordinary dose. Every coffee drinker has been running on the stuff for years without knowing its name. Rarebird’s bet: deliver it directly, skip the caffeine step, keep the alertness and lose some of what people dislike.
A WIRED reviewer who tried it in 2024 put the skeptic’s case and then conceded it. Y Combinator’s directory still carries the original and far broader line: “Elevating mental health to be a part of your daily coffee ritual.”
The gap it is aimed at
Caffeine has a long half life that varies between people, and a well known relationship with jitteriness and disturbed sleep. Decaf removes the problem by removing the point.
Founder Jeffrey Dietrich put it to AgFunderNews in 2023: “I tried decaf for a while, but it didn’t give me what I wanted.” His answer was a third category, next to regular and decaf.
He was not first to the molecule. Ingenious Ingredients self affirmed GRAS status for its enfinity paraxanthine ingredient in November 2021. Rarebird’s distinct claim is the coffee itself, and the patents are written around that.
A bioengineer who quit caffeine
Dietrich took a PhD in bioengineering at UC Berkeley in Jay Keasling’s lab, then co founded Lygos, a Y Combinator company making bio based industrial chemicals, where he was CTO for most of a decade. He left, he said, because industrial biochemicals are “a really tough space for a startup as it’s all about massive economies of scale.”
Accounts of who else founded Rarebird differ. Food Business News in April 2024 named a second co founder, AD Andracchio, formerly of Burger King, and AgFunder’s portfolio page agrees. The 2025 release and the current site name Dietrich alone. Every Form D lists Ann Dunn Andracchio as a director.
San Francisco to Winston-Salem to Buffalo
The company incorporated in Delaware in 2020 with a San Francisco address, ran lab work out of Berkeley and then San Leandro, was a Winston-Salem startup to the Triad Business Journal in April 2024, and in January 2025 moved to Buffalo after 43North selected it and put in $1 million.
The product record in between is concrete. A January 2023 Kickstarter cleared $15,000 against a $7,500 goal; first shipments went out that February; in April the Specialty Coffee Association gave a Best New Product award in the Open Class category to a Rarebird product named Redefined; a subscription launched in August. By mid 2025 the company had added instant and ready to drink formats, built an in house lab, hired a chief science officer and signed a co roasting agreement in Buffalo.
The rebrand
On September 14, 2026, a release announced that Rarebird had become NEUCAFF Performance Coffee, with Jarrod Jordan as chief executive and Dietrich moving to co founder and CTO. The positioning moved with the name, from mental wellness to human performance. Ten days later drinkneucaff.com was still serving the Rarebird storefront.
What is proven, and what is still claimed
| Evidence | What the record shows | Source type |
|---|---|---|
| US patents | Three granted to Rarebird, Inc.: 11,872,232 (Jan 2024), 12,178,820 (Dec 2024) and 12,310,971 (May 2025), plus a published application. All claim paraxanthine coffees and their production, from an April 2021 priority date. Counterparts pending in Australia, Canada and Europe. | Public record |
| Federal grants | NSF SBIR Phase I 2039060, $255,999, 2021 to 2022. Phase II 2329361, awarded June 13, 2024 and running to May 2028, $1,000,000 obligated in FY2024 and $500,000 in FY2025. Awardee of record: Revel Technologies, Inc., performing as Rarebird, Inc. | Public record |
| Grant total, as marketed | The company site says the NSF awarded it two grants “including $1M in 2025.” The NSF record puts the $1,000,000 tranche in FY2024 on an award dated June 2024, with $500,000 in FY2025. | Differs from the record |
| GRAS status | Dietrich said in 2023 that the company completed a self GRAS process in 2022 and that filing it with FDA was “not on the immediate time horizon.” FDA’s GRAS Notice Inventory returns zero records for paraxanthine, Rarebird or Revel Technologies. Self affirmed GRAS is lawful, but it carries no FDA review and no no questions letter. | Public record |
| Published safety data | One PubMed paper mentions the company: Szlapinski and colleagues, Frontiers in Toxicology, 2023. Rodent toxicity. Acute oral LD50 829.20 mg/kg; 90 day NOAEL 185 mg/kg for paraxanthine against 150 mg/kg for caffeine. Funded by Revel Technologies. | Public record |
| Human data on this product | None found. ClinicalTrials.gov lists no study sponsored by Rarebird. Human paraxanthine trials that exist tested other companies’ ingredients, not this coffee. PubMed returned no human trial with an anxiety endpoint, although the site says paraxanthine “has been shown in clinical studies to be anxiolytic.” | Not found |
| Enforcement record | No FDA warning letter names Rarebird, Revel Technologies or paraxanthine. A control search on coffee returns 25, so the search works. | Public record |
| The SCA award | SCA’s April 23, 2023 announcement lists Redefined by Rarebird, Inc. as the Open Class winner of the 2023 awards. The September 2026 rebrand release calls it “a 2025 Best New Product honor.” | Differs from the record |
| Customer evidence | 4.9 out of 5.0 from more than 345 reviews; 92 percent of surveyed buyers say they feel better than on caffeinated coffee; two thirds report better sleep. All collected by the company, none audited. Distribution is direct to consumer plus Amazon, with no named retail partner. | Company-stated |
Read plainly: the patents and the federal money are verifiable, and so is the toxicology, which is a rat safety study paid for by the company. What the record does not hold is a human trial of Rarebird’s coffee showing what it does to alertness, anxiety or sleep. The company has been careful about that in interviews and less careful in its marketing copy, and the distance between the two is the thing to watch. The FTC’s 2022 guidance is explicit that “substantiation of health-related benefits will need to be in the form of randomized, controlled human clinical testing to meet the competent and reliable scientific standard.” Nothing here treats any condition, and the company does not say it does.
What to watch
- Whether the NEUCAFF relaunch, promised for fall 2026, ships, and through which retailers.
- A human trial of the finished coffee. None is registered, and the marketing runs ahead of the evidence.
- Whether the self affirmed GRAS determination is ever filed as a GRAS notice with FDA.
- The NSF Phase II fermentation route, funded to May 2028. The paraxanthine in the product today is made synthetically.
- A Form D. Nothing has been filed with the SEC since October 2024.
In their words
“I want you to walk into every Starbucks and have this coffee.”
Jeffrey Dietrich, founder and CEO, AgFunderNews, 2023 · Interview
“It’s anecdotal, and we’re not going to make any claims about it, but that’s the kind of information you don’t get from looking at the scientific literature.”
Jeffrey Dietrich on customer reports of fewer gastrointestinal effects, AgFunderNews, 2023 · Interview
“I wouldn’t go further than saying Px’s difference from caffeine in this regard is a hypothesis developed from Px coffee drinker feedback and anecdotes,”
Jeffrey Dietrich, Perfect Daily Grind, November 2023 · Interview
“Given the quantities [of Px] used, the impact on flavour is negligible,”
Chahan Yeretzian, Zurich University of Applied Sciences, Perfect Daily Grind, 2023 · Independent
“I am always highly skeptical about functional claims like this, but Rarebird does the trick.”
Andrew Watman, WIRED review, October 2024 · Independent
“This study received funding from Revel Technologies, Inc. The funder made the decision to publish the results, but was not involved in the study design, data collection, analysis, interpretation of data, or the writing/preparation of this article.”
Funding statement, Frontiers in Toxicology, 2023 · Public record
“Starbucks is a $125 billion company because of caffeine.”
Rob LeClerc, founding partner, AgFunder, an investor, to AgFunderNews, January 2023 · Investor
“Rarebird proved there was real interest in approaching coffee and caffeine differently,”
Jeffrey Dietrich, NEUCAFF rebrand release, September 2026 · Company release
Related companies
Sources
- Public recordUS patents 11,872,232, 12,178,820 and 12,310,971
- Public recordNSF awards 2039060 and 2329361
- Public recordGRAS Notice Inventory and warning letter searches
- Public recordParaxanthine safety and comparison to caffeine, PMID 36818692
- Public recordForm D filings, CIK 0001987368
- Public recordHealth Products Compliance Guidance
- InterviewMeet the founder: Rarebird’s Jeffrey Dietrich
- IndependentRarebird serves up coffee with a splash of mental wellness
- IndependentWhat is Px coffee?
- IndependentRarebird Px Promises Alertness Without the Jitters
- IndependentIngenious Ingredients self-affirms GRAS for paraxanthine
- Certifier2023 Best New Product Awards
- CompanyCapital infusion via 43North and relocation of headquarters
- CompanyRarebird Becomes NEUCAFF Performance Coffee
- CompanyRarebird website, all product and help pages
Profile researched and written by Healthcare Discovery. Last updated September 29, 2026.
