Glycerin is a naturally-derived humectant—a substance that draws water into the skin from the air and deeper skin layers. It's a common moisturizing ingredient used across skincare products to improve hydration and skin softness.
Benefits
Increases skin hydration by attracting moisture to the outer layers
Helps maintain skin barrier function and protects against dryness
Generally well-tolerated and suitable for most skin types, including sensitive skin
Science: A comprehensive safety assessment by the Cosmetic Ingredient Review Expert Panel concluded that glycerin is safe as used in cosmetics. Research supports its role as a humectant and skin conditioning agent, and it has been studied as part of broader skincare treatments for conditions like seborrheic dermatitis.
Pentylene glycol is a humectant—a moisture-binding ingredient that helps skin retain water and feel hydrated. It's commonly used in skincare formulations to improve texture and maintain product stability.
Benefits
Draws moisture into the skin for improved hydration
Helps products feel smoother and lighter on the skin
Contributes to product preservation and stability
Potential concerns
May cause contact allergic reactions in sensitive individuals—classified as an emerging cosmetic allergen
Rare cases of contact dermatitis have been reported
Science: Safety studies show pentylene glycol has a high margin of safety in typical skincare use, with low skin penetration due to its volatility. However, recent dermatological literature identifies it as an emerging allergen capable of causing contact sensitivity in some individuals, so patch testing is recommended for those with sensitive or reactive skin.
Citric acid is a naturally occurring organic acid commonly used in skincare products as an exfoliating agent and pH balancer. It belongs to a group of acids called alpha-hydroxy acids (AHAs) that work by gently removing dead skin cells from the surface to improve skin texture and appearance.
Benefits
Gentle chemical exfoliation to remove dead skin cells
Helps improve skin texture and reduce appearance of keratoses
Can help with acne-prone skin when used appropriately
Balances product pH
Potential concerns
May cause irritation, redness, or sensitivity, especially with frequent use or in sensitive skin
Can increase sun sensitivity — sunscreen use is recommended when using AHA products
Higher concentrations may cause stinging or dryness
Science: Citric acid is a well-established AHA used in cosmetic formulations for superficial skin peeling. Research indicates AHAs including citric acid have dual effects on skin and warrant caution regarding adverse reactions, particularly with concentration and frequency of use.
