What's a Whopper? Fast-food fans looking to switch to a healthier meal can now hit the Burger King drive thru for a turkey burger.

The Miami-based company is releasing the new sandwich this week as part of its limited-time offers for spring, marking the latest fast-food effort to cater to health-conscious diners. Last week, McDonald's said it plans to offer a lower-calorie version of its Egg McMuffin made with egg whites. The Oak Brook, Ill.-based chain said the egg whites will be available for any other breakfast sandwich on its menu as well.

McDonald's and Wendy's said they have no records indicating they ever offered a turkey burger, making Burger King the biggest fast-food chain to do so.