Supplement L1 Mechanism L2 Study Patterns L3 Certainty Melatonin Regulates circadian rhythm Many RCTs on sleep latency High consistency; small samples Magnesium Glycinate Nervous system relaxation Studies show better sleep efficiency Moderate certainty Valerian Root GABA-related pathways Mixed outcomes across trials Low–moderate certainty Synthesis: Patterns show pathways involving neurotransmitter modulation and relaxation. Gaps include limited long-term studies.