So while we should always try to assess where a stock or sector is headed, the better way to trade is with a simple framework: Any stock can go up and thus be a source of profits. However, owning each stock comes with different levels of risk,

UnitedHealth Group ($UNH) stock has recently drawn strong interest from top investors and hedge fund managers, including Warren Buffett.

The company may be under criminal investigation for alleged irregularities in its Medicare business—but it's been touched by the Warren Buffett effect.