Glycerin is a naturally derived humectant—a ingredient that draws moisture from the air into your skin. It's one of the most widely used and well-studied moisturizing agents in skincare, helping skin feel softer and more hydrated.
Benefits
Attracts and retains moisture in the skin
Improves skin hydration and softness
Helps strengthen skin barrier function
Suitable for most skin types, including sensitive skin
Science: The Cosmetic Ingredient Review Expert Panel concluded glycerin is safe as used in cosmetics across all concentrations. Research shows glycerin effectively improves skin hydration and is well-tolerated with minimal irritation risk. It is also referenced in clinical guidelines for managing inflammatory skin conditions and maintaining skin integrity.
Citric acid is a naturally occurring organic acid commonly used in skincare products as an exfoliant and pH balancer. It belongs to a group of ingredients called alpha-hydroxy acids (AHAs) that help remove dead skin cells from the surface.
Benefits
Gentle exfoliation to improve skin texture and appearance
Helps reduce the appearance of keratosis and acne
Balances product pH to maintain skin compatibility
Potential concerns
Can cause irritation, redness, or sensitivity in some users, especially with prolonged or frequent use
May increase sun sensitivity — sunscreen use is recommended when using AHA products
Not suitable for very sensitive or compromised skin without caution
Science: Citric acid is an established AHA used in cosmetics for superficial peeling and skin appearance improvement, though research emphasizes that caution should be exercised due to potential adverse reactions. It is widely produced industrially and well-established in skincare formulations.
Salicylic acid is a beta hydroxy acid (BHA) that works by gently exfoliating the skin's surface and penetrating pores to remove dead skin cells and excess oil. It's commonly used in acne treatments and can help improve skin texture and clarity.
Benefits
Helps reduce acne breakouts by unclogging pores
Gently exfoliates to improve skin texture
May help fade dark spots and improve uneven skin tone when used as part of combination treatments
Potential concerns
Can cause dryness, irritation, or sensitivity, especially with frequent use or in higher concentrations
May increase sun sensitivity, so daily sunscreen is recommended
Not recommended during pregnancy without consulting a healthcare provider
Science: Salicylic acid is recognized as a first-line topical acne treatment and is considered safe for most users. Research also supports its use as an adjuvant therapy for melasma and hyperpigmentation when combined with other treatments. Start with lower concentrations and introduce gradually to minimize irritation.
Decyl glucoside is a mild, plant-derived surfactant made from natural fatty alcohols and glucose. It's used in skincare products to cleanse the skin and help other ingredients mix together, and is generally gentler than many traditional detergents.
Benefits
Mild cleansing action suitable for sensitive skin
Plant-based and renewable ingredient
Functions as an effective emulsifier to stabilize formulas
Potential concerns
Can cause allergic contact dermatitis in sensitive individuals—cases of sensitization have increased since the early 2000s
May cross-react with other similar glucoside ingredients
Can be irritating if formulation is not properly balanced
Science: The Cosmetic Ingredient Review panel concluded decyl glucoside is safe when used in non-irritating formulations at current concentrations. However, dermatology literature documents a steady rise in allergic contact dermatitis cases, particularly when it appears as a 'hidden' ingredient in sunscreens like Tinosorb M, making patch testing advisable for those with suspected sensitivities.
Benzyl alcohol is a preservative and solvent commonly used in skincare products to prevent bacterial and fungal growth, extending shelf life. It also helps dissolve and mix other ingredients together in formulations.
Benefits
Preserves product freshness and prevents microbial contamination
Helps stabilize and blend formula ingredients
Generally recognized as safe for topical use in cosmetics at approved concentrations
Potential concerns
Can cause skin irritation or allergic contact dermatitis in sensitive individuals
May cause stinging or dryness on broken or compromised skin
High systemic absorption in infants and neonates is a known concern; products containing benzyl alcohol should be kept away from babies and nursing mothers should avoid application to breast tissue
Science: Benzyl alcohol is widely used in pharmaceutical and cosmetic formulations as a preservative. Research indicates it has low systemic absorption through intact adult skin at typical cosmetic concentrations, but neonatal toxicity is a documented concern at high doses, warranting caution in products used near infants or during breastfeeding.
Cocamidopropyl betaine (CAPB) is a gentle cleanser and foaming agent derived from coconut oil. It's commonly used in shampoos, body washes, cleansers, and other rinse-off products to remove dirt and oil while creating lather.
Benefits
Effective cleansing without excessive harshness
Boosts foam and lather in rinse-off products
Helps control product thickness and texture
Potential concerns
Can cause mild skin irritation in some people, particularly with prolonged contact
Known allergen affecting 3–7% of the population; contact sensitization has increased over time
Manufacturing impurities (amidoamine, dimethylaminopropylamine) may increase allergic reaction risk
May cause eye irritation if not rinsed thoroughly
Science: Recent safety data (2024) confirms CAPB is safe at standard cosmetic concentrations (up to 30% in rinse-off products, 6% in leave-on) with a safety margin greater than 100. However, it was named Allergen of the Year in 2004 due to rising contact sensitization rates, primarily linked to manufacturing impurities rather than the ingredient itself. Most reactions are delayed allergic responses rather than immediate irritation.
Hydrolyzed rice protein is a plant-based protein derived from rice that has been broken down into smaller pieces to make it easier for skin to absorb. In skincare, it's used to help strengthen and condition the skin barrier, providing hydration and a smoother appearance.
Benefits
Helps hydrate and moisturize skin
May improve skin texture and smoothness
Plant-based alternative suitable for vegan formulations
Low allergenicity — unlikely to trigger allergic reactions
Science: Scientific evidence for hydrolyzed rice protein focuses primarily on its use in medical nutrition formulas for infants with milk allergies, where it demonstrates excellent safety and tolerability with minimal allergenicity. Direct peer-reviewed studies on its skincare efficacy are limited, though the ingredient's established safety profile in sensitive populations supports its use in cosmetic products.
Aloe vera leaf juice is a clear gel extracted from the inner leaf of the aloe plant, widely used in skincare for its soothing and hydrating properties. It's a popular ingredient in moisturizers, gels, and lotions designed to calm irritated skin and provide lightweight hydration.
Benefits
Soothes irritated or inflamed skin
Provides lightweight hydration
May help reduce redness from minor irritation or sunburn
Potential concerns
May cause contact dermatitis or allergic reactions in sensitive individuals
Latex (the yellow substance under the leaf skin) can be irritating if not properly removed during processing
Can cause photosensitivity in some people
Science: Aloe vera has a long history of use in traditional medicine and cosmetics. Limited peer-reviewed data available for this specific ingredient form, though some studies suggest aloe gel may support skin hydration and have mild anti-inflammatory properties.
Sorbic acid is a preservative used in skincare products to prevent the growth of bacteria, fungi, and mold, helping extend shelf life. It's a naturally-derived organic acid that's been safely used in food and cosmetics for decades.
Benefits
Prevents microbial contamination and product spoilage
Effective across a range of pH levels, including mildly acidic formulas
Well-established safety history in food and cosmetic applications
Potential concerns
Can cause transient redness, swelling, and irritation at concentrations as low as 0.1%, particularly on sensitive facial skin
Irritation appears to be mediated by prostaglandin response rather than allergic reaction, so it may affect most people at higher doses
May cause discomfort in individuals with sensitive or compromised skin barriers
Science: Research shows sorbic acid triggers dose-dependent erythema and edema through prostaglandin-mediated inflammation rather than immune sensitization. While physiologically inert at approved preservation levels (typically well below 0.1%), it can provoke irritation responses in human skin, suggesting careful formulation and concentration limits are important for safety.
Deionized water is purified water with minerals and ions removed, used as the main carrier and base ingredient in most skincare products. It helps dissolve and distribute active ingredients evenly throughout the formula.
Benefits
Hydrates and plumps the skin
Serves as a neutral base for other active ingredients
Helps maintain product texture and consistency
Science: Water is the most extensively studied cosmetic ingredient with a long history of safe use in skincare. Deionized water specifically minimizes mineral content that could interfere with product stability or efficacy.
