While the stimulating power of caffeine is great first thing in the morning or before a workout, it can make it tough to doze off if you're having it too late in the day, such as after 2 p.m. “Many people may be ingesting a lot more than they realize, because it’s in a lot of things besides coffee,” says Sack. Check the labels of your energy or sports drink or other supplements, such as Hydroxycut, to see if it contains the potentially sleep-wrecking ingredient.
In addition, weight-loss drugs, including inula racemosa, may contain caffeine. Other supplements, including Glycine Propionyl and L-Carnitine, may be associated with sleeplessness. Green tea (and most other kinds of tea) also contain caffeine, so be careful if you’re drinking it or taking it as a supplement. Always read the label first and discuss supplementation with your doctor.