Where glycerin sits in the Sniff System
glycerin carries a caution flag in the Sniff System. The methodology does not categorically reject it, but does penalize products where it appears in problematic concentrations, problematic combinations, or without offsetting positive ingredients.
Every methodology choice is published, citeable, and subject to revision when new evidence arrives. Read the full Sniff methodology for the formulas behind every score component, or file a correction if you think this position is wrong.
Similar ingredients in the catalog
Sniff's semantic graph clusters these ingredients near glycerin by formulation profile. Each links to its own ingredient page.