Glutathione

A tripeptide antioxidant present in all human cells, sold as an injectable and oral supplement.

What research shows

Glutathione is real biochemistry: a tripeptide central to cellular redox, with pooled human data on its levels. The cosmetic use has been assessed systematically, and injectable skin-lightening carries safety concerns that the marketing rarely mentions. Oral supplementation has randomized trials with modest findings.

Evidence strength

Highest evidence grade among the graded claims: A. Grades reflect study strength, not benefit.

Safety context

See the safety section. Absence of a flag is not evidence of safety.

No endorsement

A grade reflects evidence strength, not a recommendation to use this compound; a strong grade can attach to a harmful effect.