What brand of L-theanine is best? A comprehensive nutrition guide
                                
                                
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                                    5 min read                                
                            
                                According to a 2025 review in *ScienceDirect*, the research on L-theanine's purported benefits is still developing, though promising. However, when seeking a supplement, many people still ask: what brand of L-theanine is best, and what factors should be considered when selecting a product for relaxation and focus?