Unraveling Origins of N-Acetylcysteine (NAC): A Critical Review.

The controversial status of N-acetylcysteine (NAC) as a dietary supplement ingredient has renewed interest in its origin. This opinion article critically examines the scientific literature to investigate whether NAC is a naturally occurring compound, with a particular focus on its potential presence in plants. The primary objective of this opinion is to determine the natural occurrence of NAC, specifically within herbal matter. The classification of NAC as a dietary ingredient falls outside the scope of this analysis. We will rigorously evaluate the methodologies implemented in establishing NAC's presence in plant or herbal sources, specifically in Allium species which are often touted to contain NAC. By analyzing the strengths and weaknesses of prior research, we aim to clarify the evidence supporting the origin of NAC.