TikTok user Suzie found the card inside her McDonald's deliver order
Her DoorDash driver had added an advertisement for Herbalife with the message, 'Lose weight, ask me how!'
Herbalife is a multi-level marketing company that develops and sells dietary supplements
It has been criticized as a 'sophisticated pyramid scheme'; in 2016, it paid a $200 million fine as part of a settlement with the U.S. Federal Trade Commission
DoorDash called the driver's behavior 'inappropriate and unacceptable' and said it violates the company's policy
They said they are looking to identify the driver and take action