Every year, more than 100,000 Americans undergo chelation, most at the hands of alternative-medicine practitioners. Sick, desperate, and uninformed or misinformed, they believe that “cleansing” their blood via chelation will address conditions as varied as arthritis, hormonal disorders, and cardiovascular disease. In the process of their treatment, they are cleansed not only of bodily metals, but also of a few thousand dollars.

One day in 1999, a disheveled man (Lamas describes him as resembling Lieutenant Columbo, but with heart disease) came to Mount Sinai asking whether chelation therapy was worthwhile. “Of course not,” Lamas told him. “That’s quackery. It might be dangerous, it’s certainly costly, and it’s not going to do you any good.”

But that night, Lamas found himself dwelling on his dogmatic response. “It’s not like I had a class on chelation therapy,” he told me, his eyes closing as he smiled. On the windowless walls of his office hang his Harvard degree, a certification of training from Boston’s prestigious Brigham and Women’s Hospital, and one of his many New England Journal of Medicine articles—his past work includes seminal research that changed how cardiologists use pacemakers. Earlier in his career, he said, researching an alternative-medicine practice never would have crossed his mind. In Miami, though, the culture is more “open-minded.” So he called up the National Institutes of Health and set about procuring the funds to get to the bottom of his Columbo dilemma.

Fourteen years and 55,222 infusions later, the results of Lamas’s massive chelation study were revealed to him. (As the principal researcher in a double-blind study, he did not know which treatments had contained EDTA, and which a placebo.) A definitively positive finding stood to change the way heart disease is treated: if EDTA proved beneficial and safe, it could be used to treat the half million or more Americans who survive heart attacks each year. “I’ve never been in a trial where I had such great desire for one result,” Lamas said. “There were organizations that are really focused on preventing chelation-therapy research.” He continued, “That turned my stubbornness up. So I wanted it to be positive.”

And it was positive, officially. People who received chelation after a heart attack had a 26 percent chance of another heart attack (or stroke, or hospitalization for angina, or a procedure like bypass surgery) within the next five years. People who got placebo infusions had a slightly higher risk—30 percent (a difference that’s statistically significant, but barely). Among patients with diabetes, the result was more impressive: chelation reduced deaths in diabetic heart-attack survivors by 43 percent over five years. But this subset of patients was small. And an unusually high number of people had dropped out of the study.