Aloe Barbadensis Leaf Polysaccharides

Aloe Barbadensis Leaf Polysaccharides is the purified sugar fraction pulled from the inner leaf gel of the aloe plant.

Most of what makes it useful is a molecule called acemannan; acemannan is a big chain of sugar units (mainly a sugar called mannose, with a little glucose and galactose mixed in).

These chains come in a range of sizes and carry small chemical tags called acetyl groups, and those tags are a big part of why it's active on skin.

It works on skin in a few ways:

• As a large mucopolysaccharide it is a humectant that binds water and holds it in the stratum corneum. This helps hydrate and soothe skin.
• Beyond simple moisture, the research literature shows aloe polysaccharides can calm inflammation, help fight off microbes, support wound healing, and mop up free radicals. They do this mostly by waking up immune cells (macrophages) and by nudging skin cells (fibroblasts) to multiply and make more collagen.

The Cosmetic Ingredient Review panel considers aloe ingredients safe to use.

They usually show up at 0.1% or less in real world products, but sometimes can go up to 20%. How much actual aloe that adds up to varies a lot since suppliers sell it in very different strengths.

Allergy to this ingredient is pretty uncommon; in one-patch test study of 702 patients, none showed any reaction.

There's a handful of published allergic contact dermatitis cases but these almost all involve raw, homemade, whole-leaf juice applied "as is" rather than refined cosmetic material.