Two of AlkaPic's six ingredients are natural caffeine sources: Green Tea Leaf Extract and Guarana Seed Extract. Neither is unusual in this supplement category, but it's worth understanding what each one actually contributes, since the brand doesn't publish how much of either is in a dropper serving.
Green Tea: Fast-Acting, Well-Researched
Green tea's caffeine is often paired with catechins like EGCG, and the combination has a reasonably solid research base for modestly boosting calorie burning, summarised in research on PubMed. The caffeine itself acts fairly quickly, similar to coffee.
Guarana: Slower, Longer-Lasting
Guarana seeds contain caffeine bound within a fibrous seed matrix, which some research suggests releases more gradually than free caffeine. That's the traditional case for guarana as a "sustained energy" ingredient rather than a quick spike.
Why The Combined Dose Matters
Here's the practical issue: with two caffeine sources and no published milligram amounts for either, there's no way to calculate your total caffeine intake from an AlkaPic serving. If you already drink coffee or tea, that's worth factoring in — stacking undisclosed doses of caffeine from multiple sources is how people accidentally end up over-caffeinated.
Bottom Line
Both ingredients are reasonable, precedented choices for an energy-and-metabolism formula. The missing piece is dose disclosure, which is the same gap we flagged on AlkaPic's ingredients page.