Fast food chains in search of a sales pick-me-up are back to rolling out energy drinks. The researchNew research from Citi restaurant analyst Jon Tower on Wednesday easily explains the energy drink push by fast food giants. The majority of respondents said they order food alongside their energy beverage (packaged food at 53%, prepared food at 47%). Menu display featuring Starbucks iced energy drinks at a Starbucks location in San Francisco. (Smith Collection/Gado/Getty Images) · Smith Collection/Gado via Getty ImagesBottom lineThere are two ways to think through the fast food push into energy drinks if you are an investor.