Theobromine
Theobromine is a stimulant found in the xanthine class, similar to its more popular and commonly seen alkaloid caffeine. It is so similar to caffeine, in fact, the only difference is found in that theobromine is dimethylated, while caffeine is trimethylated (caffeine features three methyl groups while theobromine features two).
Despite its close resemblance to caffeine, human studies do not show many direct benefits of this compound, and it seems likely that caffeine is the more effective and safer compound to use.
What it does
Theobromine in theory increases alertness and energy rates, however studies offer varying results when using high doses like those commonly seen in dietary supplements[1]. One study in particular compared caffeine to theobromine in regards to their effects on mood and “vigilance” and found that “theobromine failed to consistently affect mood state or vigilance, but 100mg caffeine significantly decreased lethargy/fatigue”[2].
One potential benefit to athletes however, may be that it can act as a vasodilator[3]. Enhanced vasodilation can help lower stimulant based side effects such as high blood pressure, which can present themselves when consuming high levels of caffeine via pre-workouts and stimulant fat burners.
How it works
Theobromine exerts its theoretical energy enhancement through its ability to bind to adenosine receptors, thus block those receptors from seeing adenosine. When adenosine is incapable of attaching to adenosine receptors, we experience fewer symptoms of fatigue.
Dosing
Theobromine is traditionally dosed at 200-400mg/serving, with doses as high as 1,000mg/serving being studied on humans.