Measurement of superoxide dismutase, catalase and glutathione peroxidase in cultured cells and tissue Nature Protocols Paraxanthine, a compound your body creates when it breaks down caffeine, is being touted by some as a better alternative to coffee, offering energy and focus without the jitters. Click the link A purine derivative, paraxanthine, promotes cysteine uptake for glutathione synthesis ScienceDirect Study finds Enfinity paraxanthine enhances cognitive and memory measures better than caffeine