Medifast, Inc.
A maker of meal-replacement and metabolic-health products, Medifast sells its foods and coach-guided programs under the Optavia and Trilivy brands, used by people looking to manage their weight and metabolic health. It was founded in 1980 by Dr. William Vitale, a Baltimore dermatologist who started mixing his own liquid-diet formula after struggling to source products from other providers. The name is a blend of "medical" and "fast," a nod to the medically supervised, quick weight loss the company was built around.