A landmark 2008 study funded by Unilever demonstrated that 50 mg of L-theanine increased alpha wave activity in resting participants—a finding now central to supplement marketing worldwide. But this statistic tells only half the story.
When the same dose was administered during cognitive tasks in independent laboratory research, alpha waves decreased rather than increased. Studies from 2007 and 2009 examining L-theanine’s effects during attention-demanding activities found suppressed alpha activity, suggesting the compound’s neurological action varies dramatically based on brain state.
This context-dependent effect raises critical questions about how supplement manufacturers present evidence. Marketing materials routinely cite resting-state alpha increases without acknowledging that the same biochemical changes reverse during real-world cognitive engagement. Understanding this nuance is essential for evidence-based decision-making.
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📰 Read the full article: L-Theanine and Alpha Waves: What the Research Actually Shows →
