Caffeine + L-Theanine
Energy · focus · performance
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What is Caffeine + L-Theanine?
Caffeine is the world's most widely consumed stimulant and one of the best-evidenced performance aids. By blocking adenosine receptors it increases alertness, mood, reaction time, and both endurance and strength performance, with reliable effects at 1 to 3 mg per kg of body weight (roughly 100 to 200 mg). Pairing it with L-theanine smooths the jittery edge and sharpens focus, which is why the combo is a popular nootropic stack. Tolerance builds, so cycling and avoiding late-day doses (caffeine has a 5 to 6 hour half-life that disrupts sleep) keeps it effective. Pregnant women should limit total intake to about 200 mg a day.
The most-used stimulant in the world, with strong evidence for alertness, mood, and exercise performance.
Natural food sources
Where possible, get Caffeine + L-Theanine from whole foods first. Common dietary sources include:
Common questions
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