Avobenzone vs Locust Bean Gum: which is worse?

What is Avobenzone?

Avobenzone (INCI: Butyl Methoxydibenzoylmethane) is a chemical UV filter that is the only FDA-approved broad-spectrum UVA-absorbing active sunscreen ingredient in the US that covers the full UVA spectrum (320–400 nm). It is inherently photounstable and must be combined with photostabilizers.

What is Locust Bean Gum?

Locust bean gum (LBG) is a galactomannan polysaccharide extracted from the seeds of the carob tree (Ceratonia siliqua), native to the Mediterranean. It is a fine white to yellow powder that forms a thick gel when dissolved in hot water. It synergizes strongly with xanthan gum and carrageenan to enhance gel strength.

Documented risks

Avobenzone: Avobenzone is effective and considered safe at approved concentrations (up to 3% in US OTC sunscreens). A 2019 FDA study found that several sunscreen actives including avobenzone were systemically absorbed above the 0.5 ng/mL threshold after repeated use, triggering a call for additional safety data. This does not indicate harm, but the FDA requested more studies under its proposed sunscreen monograph. Current evidence supports its continued safe use. No clear endocrine disruption or carcinogenicity at human exposure levels is established.

Locust Bean Gum: Generally recognized as safe. EFSA's Panel on Food Additives confirmed the safety of LBG in 2017, noting no concerns at current dietary exposures. It functions as a soluble dietary fiber and can have mild prebiotic effects. No significant adverse effects have been documented in human or animal studies at food-relevant doses.