James Stangle, a doctor of veterinary medicine in South Dakota, has sounded the alarm on the Impossible Whopper, which, he says, contains so much estrogen that the mock-meat burger could grow breasts on men who wolf down too many of the Burger King sandwiches.

In a recent report for Tri-State Livestock News, Stangle crunches some serious numbers. He compares the estrogen levels found in the Impossible Whopper to those in the original Whopper, based on their protein sources (beef for the original, and soy for the plant-based one). The Impossible Whopper, Stangle concludes, has 44 milligrams of estrogen compared to just 2.5 nanograms in the beef Whopper.

“Now let me refresh your metric system,” Stangle writes. “There are 1 million nanograms (ng) in one milligram (mg). That means an impossible whopper [sic] has 18 million times as much estrogen as a regular whopper [sic]. Just six glasses of soy milk per day has enough estrogen to grow boobs on a male.”