Butylene glycol is a humectant—a type of ingredient that draws water into the skin and helps it stay hydrated. It's a small, lightweight molecule commonly used in moisturizers to improve hydration without leaving a heavy feel on the skin.
Benefits
Increases skin hydration and moisture retention
Lightweight and absorbs quickly
Helps other active ingredients penetrate the skin more effectively
Science: Research demonstrates that butylene glycol, when combined with other humectants (like glycerin and hyaluronic acid) and occlusive ingredients in moisturizers, significantly improves skin hydration in both healthy skin and compromised skin conditions such as atopic dermatitis. It is recognized as a safe, effective humectant in dermatological formulations.
Sodium hyaluronate is the salt form of hyaluronic acid, a naturally occurring substance found in your skin that acts like a moisture magnet. In skincare products, it absorbs water from the environment and binds it to your skin, helping to hydrate and plump the skin's surface.
Benefits
Delivers intense hydration to the skin
Helps reduce the appearance of fine lines by improving skin moisture
Supports skin barrier function
Suitable for all skin types, including sensitive and oily skin
Potential concerns
In very dry climates with low humidity, it may draw moisture from deeper skin layers if not sealed with an occlusive product
Rare allergic reactions are possible but extremely uncommon
Science: While the provided research focuses on intra-articular injections for joint health (showing good safety and efficacy), hyaluronic acid and its salt form are well-established in dermatology for topical hydration. The molecule's safety profile is well-documented across decades of use in medical and cosmetic applications, with severe adverse reactions being extremely rare.
2-Hexanediol is a humectant and preservative booster commonly used in skincare products to help retain moisture and extend shelf life. It works by drawing water into the skin while also enhancing the effectiveness of other preservatives, allowing brands to use lower amounts of traditional preservatives.
Benefits
Hydrates and moisturizes skin by drawing in water
Helps preserve products with lower preservative levels
Works synergistically with other skincare ingredients like niacinamide
Potential concerns
May cause cell viability concerns at concentrations above 1.0% in laboratory studies
Limited real-world safety data in humans at typical skincare concentrations (usually 2-5%)
Potential environmental concern if released into water systems
Science: While 2-hexanediol is widely used as a preservative substitute for parabens, recent cytotoxicity studies raise questions about safety at concentrations commonly found in skincare products (>2%). However, these findings are from laboratory cell studies and may not directly translate to human skin application. Further human safety studies are needed to confirm real-world risk.
