Biosaccharide Gum-4

Biosaccharide Gum-4 is a naturally-derived polysaccharide—a complex carbohydrate—typically produced through fermentation. It functions as a humectant, meaning it draws water from the environment and deeper skin layers into the stratum corneum, the outermost layer of skin.This ingredient is used in skincare formulations to support hydration and improve skin feel. It appears in a relatively small proportion of skincare products, suggesting it remains a specialised rather than ubiquitous choice among formulators.

As a humectant, Biosaccharide Gum-4 works by hydrogen bonding with water molecules. When applied to skin, it attracts moisture and holds it within the outer layers, preventing it from evaporating. This helps to maintain skin hydration and can temporarily plump fine lines.Unlike occlusive ingredients that seal the skin surface, humectants are most effective in humid environments or when layered beneath moisturising creams that prevent moisture loss.

Biosaccharide Gum-4 works most effectively when skin is already slightly damp. Apply it to clean, towel-dried skin, then follow with a moisturiser to seal in hydration. It can be layered with serums and other water-based products without issue.

Generally well-tolerated across skin types. A rare case of contact sensitivity has been reported; if you have a history of sensitivities to polysaccharides or fermented ingredients, patch test first.