Emerging science demonstrates that L‐theanine and caffeine in combination can help improve attention

Abstract

Double‐blind randomized placebo‐controlled crossover studies have shown that consumption of L‐theanine combined with caffeine can help improve attention (1,2,3). Haskell et al. (1) observed that 250mg of L‐theanine and 150mg of caffeine improved aspects of cognition and mood, while either ingredient alone did not. Owen et al. (2) demonstrated that lower levels of L‐theanine (100mg) and caffeine (50mg) also improved aspects of attention and mood, while caffeine alone did not. Similarly, Kelly et al. (3) observed that 100mg of L‐theanine and 50mg of caffeine acted synergistically, improving behavioral aspects of attention as well as affecting alpha brain wave activity related to attention during task performance. In a recent double‐blind randomized crossover study, we confirmed previous findings, demonstrating improved selective attention with consumption of an iced tea beverage containing L‐theanine (97mg) and caffeine (40mg) relative to a placebo iced tea beverage (4). We conclude that there is emerging evidence showing that L‐theanine and caffeine, when consumed in combination and in amounts of 100mg of L‐theanine and 50mg of caffeine, can help improve attention.This research was supported by the Lipton Institute of Tea