L-Theanine

An amino acid found in tea with relaxant and neuroprotective effects. L-theanine is used in various fat loss supplements, primarily for its effects on mood/cognition (both alone, and synergistically with caffeine), although there is some (very) preliminary evidence that it also may have anti-obesity effects.

For more information, see the Sloan-Kettering Cancer Center article, “L-Theanine.”