Andrew Riley, a former American Airlines flight attendant, claims the ketogenic diet caused him to blow a .05 on a breathalyzer in 2019, which resulted in him getting fired by the airline, FOX13 Tampa Bay reports. Riley previously failed a separate breath test in 2013, though in that instance, he did not dispute the charge that he’d drank alcohol.
Since this is Riley’s second offense, the stakes are extremely high: the Department of Transportation dictates that a second alcohol infraction will result in a lifetime ban from working as an attendant for any airline. Riley is calling for a new alcohol detection test to be used in assessing flight attendants, and he has some facts on his side. Riley states he was not under the influence, and instead, says he’s simply guilty of being on the ketogenic diet, in which carbohydrates are replaced with fat as the body’s main fuel source. This popular diet has made way for such culinary creations as the cheeseburger casserole (with heavy cream) and the lovely phrase “keto crotch.”
Breathalyzers are demonstrably unreliable as a 2019 New York Times investigation revealed, stating the tests “sometimes generate skewed results, even though they are marketed as being precise to the third decimal place.”
Additionally, individuals in ketosis (the physical state when the body consumes fat instead of carbohydrates) have previously blown false positives on breathalyzers. As a January 2019 article in Men’s Health explains, a body in the ketogenic state will exhale isopropyl alcohol, and breathalyzers can’t reliably tell the difference between isopropyl and ethanol, the stuff that’s in booze. Though the benefits of the ketogenic diet are often overblown, if not made up completely, the diet has shown to reduce symptoms in people who experience epileptic seizures (this evidence is often used as a jumping-off point for advocates of the diet to overextend on the diet’s promise.) Riley claims to be on the keto diet as a treatment for an autoimmune disease called “Jared Disease Autobureau Syndrome,” according to Fox13 .
The overlap of ketogenic dieters and flight attendants is probably less than massive. Still, the instance of Andrew Riley could be a milestone for the future of keto diet rights, and definitely shows the limitations of breath analysis tools. Whether Riley was just gone off the fats and proteins, or actually intoxicated, is beside the point.