Lesson 1Soothin an barrier-repair actives: panthenol, niacinamide, ceramides, cholesterol, fatty acids, oat extract (Avena), an use-level guidanceDive into soothin an barrier-repair actives suited to sensitive, dehydrated skin. Learn mechanisms an use levels fi panthenol, niacinamide, ceramides, cholesterol, fatty acids, an oat derivatives within minimalist formulas.
Panthenol for soothing and barrier recoveryNiacinamide at low, tolerable inclusion levelsCeramide, cholesterol, fatty acid ratiosColloidal oatmeal and oat-derived activesCombining actives without overloading skinLesson 2Design principles fi sensitive-dehydrated skin: minimalism, low-irritancy, barrier-supportin, humectant-emollient balanceDefine core design principles fi sensitive, dehydrated skin: minimalism, low-irritancy, an barrier support. Learn fi limit actives, avoid redundancy, an balance humectants wid emollients across a streamlined routine.
Minimalist INCI lists and formula focusAvoiding common irritant and sensitizer groupsHumectant–emollient–occlusive balancingLayering strategy across a simple routinePatch testing and gradual introductionLesson 3Humectants, occlusives, an emollients: glycerin, hyaluronic acid, propanediol, squalane, esters, an fatty alcohols wid suggested use-level rangesUnderstand how humectants, occlusives, an emollients work together fi hydrate sensitive, dehydrated skin. Review glycerin, hyaluronic acid, propanediol, squalane, esters, an fatty alcohols wid practical use-level ranges.
Water-binding humectants and optimal levelsHyaluronic acid types and molecular weightsLight emollients: squalane and estersFatty alcohols for structure and mildnessBalancing humectant load to avoid tightnessLesson 4pH targetin an buffer systems: safe pH ranges fi skin, stability considerations, an ingredient compatibilityLearn fi target skin-friendly pH ranges an design buffer systems dat protect both skin an formula. Address compatibility wid actives, surfactants, an preservatives, an monitor pH drift over shelf life.
Physiological pH range and barrier impactpH needs of surfactants and preservativesSelecting acids, bases, and buffersManaging pH drift during stability testspH considerations for exfoliating activesLesson 5Preservative approaches suitable fi sensitive skin: approved preservative families, typical levels, synergists, an preservative-free risk managementReview preservative systems appropriate fi sensitive formulations. Compare approved families, typical use levels, an boosters, an understand di risks an controls needed when pursuin preservative-free claims.
Regulatory status of key preservative groupsOrganic acids and mild preservative blendsChelators and humectants as boostersChallenge testing and PET requirementsRisk of under-preservation and recallsLesson 6Fragrance an allergen strategy: fragrance-free vs masked scents, IFRA considerations, an EU/allergen declarationDevelop a fragrance an allergen strategy suitable fi sensitive skin. Compare fragrance-free, essential oils, an low-allergen blends, apply IFRA limits, an manage EU-style allergen labelin an consumer expectations.
Fragrance-free versus low-scent approachesEssential oils and sensitization riskUsing IFRA categories and maximum levelsLabeling listed fragrance allergensMasking base odors without overloadingLesson 7Gentle surfactants an mild cleansin systems: non-ionic/amine oxide/zwitterionic options an concentration guidanceLearn how fi choose ultra-mild surfactant systems fi cleansers targetin sensitive, dehydrated skin. Compare nonionic, amine oxide, an zwitterionic options, set safe use levels, an design low-foam, low-irritancy bases.
Irritation mechanisms of common surfactantsNonionic surfactants for sensitive skinAmine oxides and zwitterionic co-surfactantsDesigning low-foam, creamy cleanser basesActive surfactant level and dilution guidanceLesson 8Ingredient selection framework: prioritizin safety, evidence, an multifunctional activesBuild an ingredient selection framework dat prioritizes safety, evidence, an multifunctionality. Learn fi interpret safety data, weigh in vivo an in vitro support, an favor ingredients dat deliver several benefits at once.
Reading safety assessments and CIR opinionsEvaluating clinical and instrumental dataChoosing multifunctional emollient-humectantsSupplier documentation and quality checksDecision trees for go or no-go ingredientsLesson 9Formulation rheology an sensorial design: emulsion types (O/W, water-serum, gel-cream), viscosity modifiers, an sensory targets fi a minimalist lineMaster rheology an sensorial design fi minimalist systems. Compare O/W creams, water-serums, an gel-creams, select viscosity modifiers, an tune slip, playtime, an afterfeel fi fragile, easily overloaded skin.
Choosing emulsion type for skin conditionPolymeric versus natural thickenersSlip, playtime, and afterfeel optimizationLightweight gel-creams for dehydrationStability checks for low-oil systemsLesson 10Skin physiology an pathophysiology: barrier function, TEWL, sensitive skin triggers, an dehydration vs drynessExplore how impaired barriers, TEWL, an nerve hyperreactivity define sensitive, dehydrated skin. Learn key triggers, how dehydration differs from dryness, an what dis means fi selectin textures, actives, an surfactant systems.
Stratum corneum structure and lipid organizationTEWL, corneometry, and hydration assessmentNeurosensory hyperreactivity and stingingTriggers: surfactants, pH, fragrance, alcoholsDehydration versus true lipid dryness
