Rockstar hails from Vegas and does not let you forget it thanks to advertising campaigns featuring scantily clad women, fast cars and the invitation to “Party Like a Rock Star!” They sponsor multiple sporting events and have a partnership with Playboy. And hey, who doesn’t secretly want to be (or be with) a hot rocker? Aside from caffeine, taurine and sugar, Rockstar energy drinks contain herbs such as ginseng, ginkgo biloba and milk thistle. (The milk thistle, a liver-cleansing plant, purportedly reduces hangovers.) Rockstar comes in 16-ounce cans and just about every flavor imaginable. The original is a bewildering but appealing mix of citrus, bubble gum and vanilla — something akin to carbonated apple juice. A regular 16-ounce can of Rockstar Energy has 280 calories, 80 more calories than a can of Monster and 60 more than the same amount of Red Bull. Dieters had best opt for Rockstar's Zero Carb Energy Drink — which clocks in at 20 calories per 16-ounce can.