Lactobacillus

Lactobacillus is a gram-positive, anerobic (doesn’t like oxygen) skin-friendly bacteria. It’s the starting point for literally hundreds of ingredients that offer numerous benefits for skin, including humectant, soothing, and supporting skin’s microbiome. The types of lactobacilli used in skin care are non-living but maintain many of the probiotic benefits of the living forms.

One of the ways lactobacillus helps skin’s microbiome is by breaking down to lactic acid. This alpha hydroxy acid works with skin’s natural moisturizing factor (NMF) to maintain hydration.

While non-living lysate or ferment forms of lactobacillus are used in skin care, foods such as yogurt, kimchi, and kefir use live forms, known as probiotics. Oral consumption of living probiotics and application of non-living probiotic ferments and lysates to skin have been shown to improve its moisture content, strengthen its barrier, and reduce signs of sensitivity.

Lactobacillus and its many forms have various usage levels in cosmetics, typically between 0.1–2%, the latter being the recommended amount when lactobacillus ferment is used to augment the product’s preservative system. These strains have GRAS (generally recognized as safe) status when used in foods; as such, the much lower amounts used in cosmetics are also considered safe.