Beta glucan is a natural sugar molecule that hydrates skin, calms inflammation, supports collagen production, and strengthens the skin barrier. Found in skincare serums and creams at concentrations typically between 0.25% and 2%, it’s one of the gentler active ingredients available, well tolerated even by sensitive and eczema-prone skin.
Where Beta Glucan Comes From
Beta glucan is a polysaccharide, a long chain of sugar molecules found in the cell walls of oats, mushrooms, yeast, and other microorganisms. The version you’ll see most often in skincare is derived from baker’s yeast or oats, though mushroom-sourced forms are growing in popularity. Each source produces a slightly different molecular structure, which can affect how the ingredient behaves on skin. Yeast-derived beta glucan, for example, tends to be especially effective at stimulating immune responses in the skin, while oat-derived versions are known for their soothing properties.
How It Hydrates Skin
Beta glucan works as a humectant, meaning it draws water into the outermost layer of skin and holds it there. Its fibrous structure lets it form a thin, continuous film on the surface that limits water evaporation throughout the day. But unlike moisturizers that only sit on top of the skin, beta glucan also works deeper by promoting lipid production and supporting the process by which new skin cells mature. This gradually rebuilds the skin’s natural moisture barrier rather than just temporarily masking dryness.
People often compare beta glucan to hyaluronic acid, which can hold up to 1,000 times its weight in water. No head-to-head clinical study has directly compared the two ingredients for hydration. They work through different mechanisms, though: hyaluronic acid acts mainly as a water reservoir in the skin, while beta glucan focuses more on reinforcing barrier function and reducing inflammation. The two pair well together in a routine for that reason.
Skin Barrier Repair and Soothing
One of beta glucan’s strongest roles is calming reactive, irritated skin. It influences how the immune system responds locally, dialing down the kind of low-grade inflammation that causes redness, stinging, and flaking. In a multicenter study of 105 people with atopic dermatitis (eczema), applying a cream with just 0.25% beta glucan two to three times daily improved symptoms on treated skin compared to areas receiving only a standard moisturizer. A separate trial had 13 people with self-reported sensitive skin apply a formula containing 0.5% to 2% beta glucan twice daily for six weeks and found measurable improvements in skin comfort and resilience.
This barrier-repair ability makes beta glucan especially useful if your skin reacts easily to other active ingredients like retinol or exfoliating acids. It’s not treating the underlying condition the way a prescription would, but it creates a stronger, less reactive surface that’s better equipped to handle environmental stress.
Collagen Support and Anti-Aging Effects
Beta glucan stimulates fibroblasts, the cells responsible for producing collagen and elastin in deeper skin layers. Research shows it increases the activity of genes involved in making procollagen, the precursor your body assembles into mature collagen fibers. It also has antioxidant properties that help protect existing collagen from breaking down under UV exposure and pollution.
In one clinical trial, 20 men with visible signs of skin aging applied a 1.5% beta glucan formula twice daily for 16 weeks. By the end of the study, they showed significant improvements in both skin firmness and hydration. These aren’t dramatic overnight changes. Four months of consistent use is a realistic timeline for noticing firmer, more resilient skin texture.
Wound Healing
Beta glucan has a well-documented ability to speed wound repair, which is part of why it shows up in post-procedure skincare and burn treatment. It works by attracting macrophages (immune cells that clean up damaged tissue) to the wound site, which in turn stimulates new tissue growth, collagen deposition, and the regrowth of surface skin cells.
A clinical study on burn patients compared a 5% beta glucan ointment applied daily against a standard wound-healing product. After up to four weeks of treatment, 57% of patients using the beta glucan ointment had completely healed wounds, compared to just 10% in the control group. In chronic venous ulcers, beta glucan dressings achieved an 87% reduction in ulcer size versus 56% with standard care over 90 days, with 79% of patients rated as having excellent cosmetic outcomes. While most people aren’t using beta glucan for open wounds at home, this healing capacity translates to faster recovery from minor cuts, acne lesions, and post-treatment skin.
What Concentration to Look For
Clinical studies have used beta glucan at concentrations ranging from 0.25% to 5%, depending on the application. For everyday skincare, products in the 0.5% to 2% range have shown clear benefits for hydration, sensitivity, and firmness. The 0.25% concentration used in the eczema study still produced results, so even lower-dose products can be effective for soothing purposes. Higher concentrations around 5% are generally reserved for wound care rather than cosmetic use.
Most skincare brands don’t disclose the exact percentage of beta glucan in their formulas, so look for it in the top third of the ingredient list if you want a meaningful concentration. It’s listed as “beta glucan,” “beta-glucan,” or sometimes “saccharomyces/oat beta glucan” depending on the source. You’ll find it in serums, moisturizers, and sheet mask essences.
Tolerance and Compatibility
Beta glucan is one of the least irritating active ingredients in skincare. Across clinical trials involving sensitive skin, eczema patients, and burn wounds, no significant adverse reactions have been reported. It works well alongside most other ingredients, including retinoids, vitamin C, niacinamide, and chemical exfoliants. If your skin is too reactive for stronger actives, beta glucan can serve as a calming base layer that helps your skin tolerate more of your routine over time. Twice-daily application (morning and evening) is the schedule used in most studies and is a reasonable starting point.