Medifast offers multiple ways to lose weight: it develops personal diets, counsels clients and sells healthy meals and snacks. The company celebrated its 30-year anniversary in 2010 by beefing up profits 73%. Revenue at its Take Shape for Life personal coaching division, which accounts for 65% of Medifast's total, increased by 62%. ("Coaches," in Medifast parlance, are local folks-roughly in the mold of the Avon Lady-who collect commissions on products sold and can get a bonus in their first month for acquiring new customers.)

The company, which now has 80 Medifast Weight Control Centers, opened 15 new centers this year alone. It also recently expanded its "Medifast to go!" product line and last year added desserts, introducing the Medifast Brownie, which is billed as a full-meal replacement with real chocolate chips.