When my dad was a 12-year-old kid in Red Bluff, California, circa 1928, part of the extended family was a man he knew as Uncle Jack Cotney. That they knew of, or he'd admit to, Uncle Jack had survived some 25 stand-up gunfights in his life.
Green tea is a fat burner that does speed up the metabolism, as far as energy drinks however they really speed up the heart not your metabolism. If you're looking for something that will speed up your metabolism there are better choices for that. Good Luck, Casey.
Sugar crashes, energy slumps and caffeine withdrawal. According to the infographic, caffeine enters the bloodstream within 10 minutes of consuming an energy drink, triggering a rise in heart rate and blood pressure. Over the next 15-45 minutes, caffeine levels in the bloodstream peak.