Gluconolactone
Gluconolactone is a polyhydroxy acid (PHA) with more talents than exfoliation alone. It is similar in functionality to alpha hydroxy acids (AHAs) but is considered gentler due to its larger molecular size.1 Like all acids, PHAs stimulate skin’s repair process while lessening the appearance of fine lines, inflammatory imperfections, and age spots. Gluconolactone is an effective chelating agent (binds to metals and helps stabalise formulas) and may also function by scavenging free radicals (antioxidant), thereby protecting skin from some of the damaging effects of UV radiation.2
Gluconolactone doesn’t seem to increase skin’s susceptibility to sunburn as significantly as AHAs, and it may help repair existing cutaneous photodamage.2 It by no means, however, replaces the need to wear broad spectrum sunscreen daily. PHAs are a great option for all skin types and have proven to work well from light to deep skin tones.1
references
[1] Grimes PE, Green BA, Wildnauer RH, Edison BL. The use of polyhydroxy acids (PHAs) in photoaged skin. Cutis. 2004 Feb;73(2 Suppl):3-13.
[2] Bernstein, E.F., Brown, D.B., Schwartz, M.D., Kaidbey, K. and Ksenzenko, S.M. (2004), The Polyhydroxy Acid Gluconolactone Protects Against Ultraviolet Radiation in an In Vitro Model of Cutaneous Photoaging. Dermatologic Surgery, 30: 189-196. doi:10.1111/j.1524-4725.2004.30060.x