Corn syrup, especially High Fructose Corn Syrup, gets a bad rap. It's no worse than sugar. As long as you keep all carbohydrates low, and eat within your TDEE, you're good.  I remember reading how the use of HFCS actually peaked in the early 2000s, and has been dropping in use while everything else continues rising. So it's not solely the fault of corn syrup, it's just a major ingredient in many of the stupid snacks the beetus betties enjoy.