The medical sensation of the decade is a set of drugs that help people slim down. With weekly injections, people can drop 15 percent to more than 22 percent of their body weight on average, often 40, 50 pounds — or more. No safe medicine or any other weight-loss strategy except surgery has been so effective. Given that nearly 42 percent of Americans are obese, and thus vulnerable to diabetes, heart disease, stroke and various kinds of cancer, Wegovy, Zepbound and other so-called GLP-1 agonists come as a breakthrough. They offer a way to vastly improve public health — not to mention quality of life among people who struggle to lose weight.