When most people think about health care, rarely do "discounts" and "low prices" come to mind. But Walmart is looking to change that. The retail behemoth, which markets itself as the leader in "Everyday Low Prices," is beefing up its presence in the health care sector. It inked a deal last month with Anthem, one of the nation's largest insurers, to entice more Medicare enrollees to buy over-the-counter medications and health supplies at its stores. It recently tapped former Humana executive Sean Slovenski to lead its health and wellness division. And it was reportedly looking to buy PillPack before Amazon purchased the online pharmacy in June. Walmart is one of the latest -- and largest -- retailers to expand its reach into the fast-growing and lucrative health care arena, which makes up 18% of the nation's economy and is growing. Amazon is also ramping up its health care offerings, and CVS is purchasing Aetna to expand its services.