What it is
Succinic acid is a naturally occurring four-carbon dicarboxylic acid that appears in metabolic pathways throughout living organisms. In formulations it is used mainly to adjust and stabilize pH and as part of buffering systems, and it can also serve a minor skin-conditioning role. It is typically used at low levels.
Safety & warnings
Succinic acid is generally well tolerated at the low levels used for pH adjustment. As an acid it is handled within buffered systems so the finished product stays at a skin-compatible pH. It is not an oil and is not considered comedogenic.
Origin & sourcing
Can be obtained by fermentation or produced synthetically; cosmetic-grade material is a well-defined, purified compound.
Questions everyone asks
Why is succinic acid in a sunscreen?
It is used mainly to adjust and stabilize the product's pH as part of a buffering system.
Is succinic acid an exfoliating acid?
It is used in cosmetics chiefly for pH control rather than as an exfoliating acid like glycolic or salicylic acid.