Kim Kardashian and her sisters Khloe and Kourtney have their faces and names on numerous items on the market. They endorse everything from clothes to fragrances to jewelry. One endorsement deal that is backfiring on the ladies is their QuickTrim diet products. According to TMZ, some New Yorkers are saying that it is impossible to claim that the Kardashians lost weight with the help of QuickTrim due to caffeine being its main ingredient. The $5 million lawsuit also states that the FDA seems to be backing the plaintiffs' accusations, as they have determined that caffeine "is not a safe or effective treatment for weight control."

See the full story on TMZ.com.