The Science of Flavored ENDS: A Response to Bloomberg, Durbin, and the Senate Letter on FDA’s Recent Actions

The stakes: half a million American lives every year

Cigarette smoking kills roughly 480,000 Americans annually, and nearly 28 million American adults still smoke. Peer-reviewed population modeling estimates that displacing combustion with substantially less harmful nicotine delivery would avert between 1.6 and 6.6 million premature deaths and recover 20.8 to 86.7 million life-years by 2100. A series of recent opinion pieces (Bloomberg op-ed and Senator Dick Durbin’s (D-Ill.) STAT News opinion) and a letter signed by ten Senators (the Blumenthal-Merkley letter) focus on the risks of non-combustible nicotine products to youth and non-smokers while lambasting the Food and Drug Administration (FDA).

A serious tobacco harm reduction (THR) framework supports three goals simultaneously:

• Accelerates substitution for current smokers.
• Prevents youth initiation of nicotine use through Tobacco-21 (T21), which bans the sale of all tobacco products to anyone under 21, and risk-proportionate authorization.
• Gives those who smoke fair and unbiased information about relative risk.

The aforementioned recent commentaries treat these goals as if they were in tension. The published evidence suggests that the goals are mutually reinforcing when policy is calibrated to the science.

What the FDA actually did

On May 5, 2026, the FDA authorized four Glas closed-pod electronic nicotine delivery system (ENDS) products, including the first two non-tobacco, non-menthol flavored ENDS ever granted marketing orders under the “appropriate for the protection of the public health” (APPH) standard. Additionally, on May 8, the FDA finalized an enforcement-priorities guidance clarifying that the agency will not prioritize action against ENDS and nicotine pouch products whose premarket tobacco applications have been accepted and are pending.

This action does not apply to products that display youth-appealing design elements such as cartoon characters, toy-like form factors, cotton-candy and bubblegum descriptors, excessive nicotine, or inadequate child-resistant packaging. No categorical flavor ban was reversed because none ever existed in statute. The Supreme Court’s unanimous 2025 decision in FDA v. Wages and White Lion Investments affirmed the FDA’s authority to deny applications that fail the APPH bar, and the same logic compels the authorization of applications that meet it.

Flavored ENDS and adult cessation

The most recent Cochrane systematic review reports high-certainty evidence that nicotine e-cigarettes outperform nicotine-replacement therapy for smoking cessation (risk ratio 1.59, 95% CI 1.29 to 1.93), a finding replicated in a randomized clinical trial published in the New England Journal of Medicine. Additional research suggests that adults who use non-tobacco flavored ENDS were more likely to quit smoking compared to those who used tobacco-flavored ENDS. Research hasshown that state flavored-ENDS restrictions result in an 80 percent reduction in daily young-adult vaping, accompanied by a 22 percent increase in daily smoking, evidence of substitution, back into combustion. A product that nearly triples quit odds in randomized trials is the opposite of the “Marlboro playbook” Senator Durbin invokes.

The toxicant comparison is the wrong one

Sen. Durbin lists formaldehyde, chromium, nickel, and lead among ENDS constituents. Biomarker data show exclusive ENDS users carry 10 to 98 percent lower internal concentrations of tobacco-related toxicants than combustible-cigarette smokers, consistent with Public Health England’s estimate that vaping is around 95 percent less harmful than smoking. The relevant comparator for an adult smoker is the cigarette already in their hand, not a hypothetical zero-exposure baseline.

Youth use is declining, and T21 is why

The 2024 NYTS reported 1.63 million current middle- and high-school e-cigarette users, 5.9% overall; the high-school rate was 7.8%. Federal T21 took effect in December 2019. The 2015 Institute of Medicine projected a 25 percent reduction in smoking initiation among 15- to 17-year-olds under a nationwide T21 policy, and post-implementation studies have documented reduced retail access and lower smoking participation among older adolescents in covered jurisdictions. T21 disrupts the social-supply chain through which most underage use occurs. Flavor prohibition does not.

The gateway claim and the unintended-consequences problem

Prospective cohort evidence suggests that the apparent ENDS-to-cigarette progression is largely explained by shared risk factors for any nicotine use, not by a causal pharmacologic gateway. 

An analysis of the Population Assessment of Tobacco and Health (PATH) cohort identified an apparent relationship between e-cigarette use and current cigarette smoking among youth. The suggested patterns of ENDS use leading to cigarette use disappear after accounting for shared vulnerability, meaning the association cited as evidence of a gateway effect is attributable to confounding factors rather than to any causal effect of vaping on continued smoking. A separate analysis of the same cohort found that e-cigarette use was not significantly associated with later cigarette smoking, either directly or through nicotine dependence, while the reverse pathway from cigarettes to e-cigarettes was significant, a pattern consistent with smokers using ENDS as a reduction tool rather than with vaping causing smoking. 

Population-level simulation modeling of US National Youth Tobacco Survey data shows that observed adolescent smoking trends cannot be reproduced by any effect of ENDS use on cigarette initiation, and that matching the actual decline requires a substantial diversion effect that exceeds any opposing effect. The evidence at the population level is consistent with this: the youth cigarette-smoking decline has accelerated during the period during which ENDS prevalence rose sharply. Once youth use of ENDS products was curtailed (due to T21), vaping rates plummeted, and youth smoking now sits at 1.7 percent, the lowest level on record.

Studies have also shown that flavored-tobacco bans produced a measurable increase in combustible smoking. Modeling of menthol-cigarette prohibition projects that 69 to 100 percent of displaced demand migrates to illicit markets. State enforcement officers are already absorbing the cost of an unregulated illicit-vape market that flavor prohibition would enlarge, not shrink. The costs of banning flavored products clearly outweigh the perception of safety that proponents of banning reduced-risk products envision.

The enforcement guidance is targeted, not permissive

The May 8 guidance explicitly targets the cotton-candy and bubblegum descriptors Sen. Durbin invokes as protected, removes products with cartoon imagery and toy-like form factors from the enforcement-discretion list, and publishes a public product registry for retailers and state enforcement officers. It is the operational complement to the Glas authorization, not a contradiction of it.

International evidence

Sweden, the United Kingdom,Japan, and New Zealand have driven smoking rates to historic lows by authorizing credible reduced-risk alternatives, holding youth use down through targeted access controls, and communicating relative risk honestly to adult consumers. Countries that prohibited reduced-risk products and relied on combustion-only abstinence messaging have stagnated or regressed. The choice is empirical, not ideological.

The disagreement is about the process, not the goal

Sen. Durbin’s account of losing his father to lung cancer at 53 is genuine, and every THR advocate shares his goal of sparing other families that loss. The disagreement is about the process. The single most powerful intervention available to reduce smoking-related mortality today is to accelerate substitution of combustion among the 28 million adults who still smoke. Prohibiting the products that drive that substitution, in the name of protecting children whose use is at historic lows, maximizes the deaths all are working to prevent. The American public health community can save approximately half a million lives every year if it has the discipline to authorize what works, restrict access for children, and tell smokers the truth. Now that the FDA is finally acting based on the science, the science is on its side.