THE NEWS: Monster Beverage Corp. disclosed in a regulatory filing Thursday that it’s being investigated over the advertising and ingredients of its energy drinks. The company provided little detail, saying the investigation was in its early stages.

THE BACKGROUND: Energy drinks have been surging in popularity in recent years, particularly among younger consumers. Their growing popularity has also raised concerns about the caffeine levels in the drinks. They can have more than three times as much caffeine than soda such as Coca-Cola or Pepsi.