Consumer Reports released results Tuesday.
The company that makes 5-hour Energy says people drink it more than 7 million times a week. Consumer Reports wanted to know if it really can prevent an afternoon slump. It contains B vitamins and 1,870 milligrams of what it calls an "energy blend" - a long list of ingredients including caffeine.
Consumer Reports says 5-hour Energy, which costs about $3 a shot, will probably chase away grogginess, but so will a cup of coffee, and it costs a lot less. The label cautions that women who are pregnant or nursing should not try it, as well as children under 12.