What it is
Calcium gluconate is a water-soluble calcium salt of gluconic acid that appears as a white powder. In skin care formulas it is used to help bind metal ions and support overall formula stability, and it can contribute calcium to the formulation. It is included at low levels and has no color or odor impact.
Safety & warnings
Calcium gluconate is widely used and considered well tolerated at cosmetic levels, with a low likelihood of irritation. It is not a fragrance allergen and is not associated with comedogenicity.
Origin & sourcing
It is produced synthetically by neutralizing gluconic acid, which is typically derived from the fermentation of glucose, with a calcium source.
Questions everyone asks
What does calcium gluconate do in a sunscreen?
It mainly acts as a chelating agent that binds trace metal ions to help keep the formula stable, and it can provide a source of calcium and minor buffering.
Is calcium gluconate the same as gluconolactone?
No. They are related to gluconic acid, but calcium gluconate is a calcium salt used for chelation, while gluconolactone is a polyhydroxy acid used differently.