🎀Hydrating Hair Serum – Leave-In Conditioner with Keratin, Biotin, Castor & Rosemary Oils

🎀Hydrating Hair Serum – Leave-In Conditioner with Keratin, Biotin, Castor & Rosemary Oils

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🎀Hydrating Hair Serum – Leave-In Conditioner with Keratin, Biotin, Castor & Rosemary Oils

🎀Hydrating Hair Serum – Leave-In Conditioner with Keratin, Biotin, Castor & Rosemary Oils

$26.99
$26.99
SAVE Sold out
Nutra Harmony Professional Care
“The hair serum category is overcrowded with products that address one problem by creating another: the anti-frizz serum that weighs fine hair flat, the hydrating conditioner that makes oily roots oilier by the end of the day, the heat protectant that coats the hair in a silicone film that prevents moisture absorption for the next 48 hours. The practical failure of single-benefit hair products is that hair has multiple concurrent needs — a strand that is simultaneously dry, frizzy, color-treated, and heat-styled needs nourishment, frizz control, color protection, and thermal shielding in the same session. A leave-in serum that addresses all six of these need categories with a non-greasy, rapidly absorbed formula, usable on wet or dry hair, represents a genuine consolidation of what most people use three to four separate products to achieve.”

1 Serum. 6 Benefits. 3 Ways to Use. Nutra Harmony Hydrating Hair Serum — 150ml — Keratin + Biotin + Castor & Rosemary Oils + Wheat Protein + Vitamins B & E — Anti-Frizz — Heat Protection — Leave-In — Paraben & Sulfate-Free — Cruelty-Free.

The Nutra Harmony Hydrating Hair Serum is a leave-in treatment formulated to address the full spectrum of everyday hair concerns in a single application — nourishing, hydrating, smoothing, repairing, defrizzing, and protecting. The formula combines Keratin for structural strength and shine, Argan Oil for smoothness and brilliance, Rosemary Oil for scalp and strand invigoration, and Wheat Protein for volume and thickness, supported by Biotin, Castor Oil, and Vitamins B & E. The non-greasy, easily absorbed formula works on wet hair, dry hair, and as a heat protection base before blow-drying or straightening — covering the three primary moments in any hair care routine where a treatment product would be applied. 5 OZ / 150ml. Paraben-free, sulfate-free, cruelty-free. Dermatologically tested. 100% recyclable packaging.

💧 Deep Hydration  ·  🪶 Frizz Control  ·  ✨ Repair & Shine  ·  🛡️ Heat Protection  ·  🌿 Keratin + Biotin + Castor & Rosemary  ·  🚫 Paraben & Sulfate Free  ·  🐰 Cruelty-Free

Nutra Harmony Hydrating Hair Serum 150ml anti-frizz leave-in conditioner keratin biotin castor rosemary oil deep purple bottle gold pump professional care cruelty sulfate free
Key Ingredients

🌿 4 Active Ingredients + 3 Supporting Actives. Every One With a Specific Job.

🧶 Keratin — Structural Strength & ShineKeratin is the primary structural protein that makes up the cortex of the hair shaft — hair damage from heat styling, chemical treatments, and environmental exposure progressively degrades the keratin matrix, creating the porous, rough surface texture that manifests as frizz, breakage, and dullness — topically applied keratin bonds to the damaged sites on the hair shaft surface, filling the gaps in the cuticle layer that scatter light and cause frizz, while restoring the smooth cuticle surface that reflects light directionally and produces the shine associated with healthy hair — keratin is the only ingredient that directly addresses the structural cause of frizz rather than coating the strand in a film that temporarily masks the underlying porosity damage.
🪴 Argan Oil — Smoothness & BrillianceArgan oil is a lightweight, non-comedogenic plant oil with a fatty acid profile (predominantly oleic and linoleic acid) and a high vitamin E content that makes it the benchmark emollient for hair serums — at the molecular level, argan oil penetrates the hair shaft’s lipid layer and restores the inter-fiber lipid content that heat and chemical processing strip away — the practical effect is a significant reduction in surface roughness and a corresponding improvement in the hair’s reflectance — argan oil is also one of the lightest plant oils, which is why an argan oil-based serum can deliver emollient benefits without the greasy residue that heavier oils (coconut, olive) leave on fine or medium hair when used as leave-in treatments.
🌿 Rosemary Oil — Invigoration & Scalp HealthRosemary oil contains the active compounds ursolic acid and rosmarinic acid, which have documented effects on scalp circulation and follicle health at topical application — the invigoration effect of rosemary oil is the result of its mild vasodilatory action on scalp surface blood vessels, increasing nutrient and oxygen delivery to the hair follicles during the period of application — for the hair strand itself, rosemary oil provides a conditioning effect and a characteristic fresh, herbaceous scent that contributes to the serum’s overall soft floral fragrance without requiring additional synthetic fragrance compounds at high concentrations — the antioxidant activity of rosemary’s phenolic compounds also contributes to the formula’s stability by reducing oxidative degradation of the other oil ingredients.
🌾 Wheat Protein — Volume & ThicknessHydrolyzed wheat protein is a film-forming protein that deposits on the hair shaft surface and penetrates the damaged cuticle to increase the hair shaft’s effective diameter — the volume and thickness claim is the direct mechanical result of this diameter increase: hair strands that have been treated with wheat protein are physically slightly thicker than they were before treatment, which produces the volume and plumping effect without the synthetic polymer buildup that volumizing styling products typically rely on — the protein film also reinforces the cuticle layer against mechanical damage from combing and heat styling, contributing to the serum’s repair function alongside the keratin structural repair mechanism.
🌻 Biotin (Vitamin B7) — Radiance & Thickness SupportBiotin at topical application supports the keratin infrastructure production pathway at the follicle level — the clinical evidence for biotin in hair thickness and radiance is primarily from supplementation studies, but topical biotin in a leave-in serum provides a localized concentration at the follicle and strand surface that supports the appearance of thickness and shine — biotin is included in this formula as a supporting active alongside the keratin structural repair mechanism, providing the follicle-level support that complements the strand-level strengthening from the topically applied keratin.
🌺 Castor Oil + Vitamins B & E — Nourishment & Breakage ReductionCastor oil (Ricinus communis) is a high-viscosity plant oil with a ricinoleic acid content above 85%, giving it exceptional lubricating properties at the hair shaft surface — the lubrication effect reduces the mechanical friction between hair fibers during combing and styling, which is the primary mechanical cause of breakage in dry and damaged hair — Vitamin E (tocopherol) is an antioxidant that protects the hair’s lipid layer from UV and heat-induced oxidative degradation, while Vitamin B (panthenol, B5) penetrates the hair shaft and holds moisture by attracting and retaining water molecules within the cortex — together these supporting actives address the nourishment and breakage reduction claims from multiple simultaneous mechanisms.
6 Benefits in 1 Bottle

✨ Nourishing. Hydrating. Smoothing. Repairing. Defrizzing. Protecting. All Six, Every Session.

🌿
NourishingKeratin, Argan Oil, Castor Oil, and Vitamins B & E deliver the nutritive components that chronically dry and processed hair is depleted of — the nourishment benefit is cumulative with consistent daily use, with the most significant improvement visible after 2–3 weeks of regular application
💧
HydratingPanthenol (Vitamin B5) and the water-phase components of the serum bind moisture within the hair cortex and prevent the moisture loss that causes the brittle, snapping breakage pattern of dehydrated hair — visible from first use on very dry hair as a reduction in static and improved detangling ease
✨
SmoothingArgan Oil’s emollient action on the cuticle surface layer and Keratin’s gap-filling repair of the cuticle structure combine to produce a measurably smoother hair surface — the smoothing benefit is the primary driver of the improved shine, reduced tangling, and easier combing-out that users notice immediately after first application
🔧
RepairingKeratin and Wheat Protein directly repair the structural damage to the hair shaft’s cuticle and cortex layers — this is not a cosmetic coating but a chemical repair: the keratin peptides bond to the broken disulfide linkages on the damaged hair surface, reducing the porosity that causes frizz and the structural weakness that causes breakage and split ends
🪶
DefrizzingFrizz is caused by a combination of cuticle porosity (which allows humidity to penetrate the hair shaft unevenly) and surface roughness (which traps fiber-to-fiber friction in a way that makes individual hairs stand away from the strand mass) — the serum addresses both simultaneously: Keratin reduces porosity, Argan Oil reduces surface roughness, and the combined effect is visible frizz reduction that lasts through the day
🛡️
ProtectingHeat protection from the thermal buffer layer created by the serum’s oil phase between the hair shaft and the heat source — UV protection from Vitamin E’s antioxidant shielding of the hair’s lipid layer against UV oxidation — environmental protection from the sealed cuticle surface that resists humidity, pollution particle adhesion, and the mechanical damage from wind and friction
3 Ways to Use

💪 On Wet Hair. On Dry Hair. Before Heat Styling. One Serum for All Three Moments.

💧 On Wet Hair — Deep Hydration & NourishmentApply immediately after washing and towel-drying, before any heat tool or air-dry session — wet hair has the cuticle slightly raised and the hair shaft at its most absorbent state, making this the highest-bioavailability moment for the keratin, protein, and oil actives to penetrate — on wet hair the serum’s hydration actives (panthenol, castor oil) are absorbed into the open cuticle, improving moisture retention throughout the dry-down process — adds smoothness, silkiness, and elasticity — this is the recommended application sequence for maximum repair and hydration benefit
🪶 On Dry Hair — Anti-Frizz Control & DetanglingApply to dry hair as a midday frizz-control or detangling treatment — for dry application, use a smaller amount than the wet-hair application (a peanut-size amount is sufficient for mid-length dry hair) and distribute through the mid-lengths and ends, avoiding the scalp root zone to prevent any appearance of weight — the argan oil and keratin actives work on the surface of the already-dry cuticle to smooth and seal flyaways without requiring the hair to be re-wetted — adds softness, controls frizz, and restores shine to hair that has dried with unwanted texture
🔥 Before Heat Styling — Thermal Protection BaseApply to damp or dry hair as the last step before blow-drying, flat ironing, or curling — the serum’s oil phase creates a thermal buffer layer on the hair shaft surface that absorbs and dissipates heat energy before it reaches the hair cortex — the heat protection function reduces the temperature at the hair surface during tool contact, limiting the keratin denaturation and moisture vaporization that are the primary mechanisms of heat-induced hair damage — protects against blow-drying, hair ironing, and UV exposure — always apply before the heat tool is in contact with the hair, not after
Heat Protection

🔥 Blow Dryer. Flat Iron. UV. The Thermal Buffer That Stands Between the Heat and Your Hair.

Nutra Harmony hair serum heat protection blow drying flat iron UV damage shield keratin thermal buffer before after heat styling damage prevention
🔥 How Heat Damages HairWhen a blow dryer or flat iron contacts the hair shaft, the surface temperature can reach 200–230°C (390–450°F) at the iron plate — at these temperatures, the keratin proteins that form the hair’s cortex begin to denature (their molecular structure unfolds irreversibly) — the moisture within the hair shaft vaporizes rapidly, leaving behind a dehydrated, porous structure that is more susceptible to mechanical breakage and further heat damage in subsequent styling sessions — the cumulative result of unprotected daily heat styling is the progressive thinning, brittleness, and split-end formation that characterizes heat-damaged hair after several months of regular flat iron or blow dryer use at high temperatures.
🛡️ How the Serum ProtectsThe serum’s oil phase (Argan Oil, Castor Oil, Rosemary Oil) creates a continuous film on the hair shaft surface that functions as a thermal buffer — the oil film has a significantly higher heat capacity than the air surrounding the hair, meaning it absorbs and dissipates heat energy more slowly — by the time the heat conducts through the oil film to the hair shaft surface, its intensity has been reduced below the threshold at which keratin denaturation and moisture vaporization occur — the Vitamin E component contributes UV protection by absorbing UV radiation before it reaches the hair’s lipid layer, preventing the oxidative degradation of the hair’s structural lipids that UV exposure causes during outdoor time.
💡 Heat Protection Application Sequence:
— Apply before heat tools — never after: the protective oil film must be in place on the hair shaft surface before heat contact — applying after heat is applied provides no protective benefit and may increase residue without any thermal protection function.
— Distribute evenly to ends: the ends of the hair shaft are the oldest, most heat-damaged, and least protected by the scalp’s natural sebum — ensure the serum reaches the full length of each strand, not just the mid-shaft.
— Do not apply to soaking-wet hair before blow-drying: apply after towel-drying to damp (not soaking) hair — excess water on the hair surface reduces the serum’s ability to coat the cuticle evenly before the heat tool contact begins.
How to Use & Dosage Guide

🪶 Apply. Comb Through. Style. The Correct Amount Makes the Difference.

  1. Choose Your Application Moment — Determine whether you are applying to wet hair (for maximum hydration and repair benefit), dry hair (for frizz control and detangling), or before heat styling (for thermal protection) — all three applications use the same serum — the application sequence and the amount dispensed vary by use case — for wet-hair and heat-protection applications, the serum is applied before heat or drying — for dry-hair frizz control, it is applied to already-dry hair as a finishing step.
  2. Dispense the Correct Amount for Your Hair Length — The amount of serum dispensed is the most important variable in achieving the hydration and smoothing benefit without any residue or heaviness — more is not better: excess serum does not increase the benefit and will leave the hair looking oily rather than healthy — use the hair-length dosage guide below as your starting point and adjust by half-a-portion up or down based on your hair density (fine hair needs less than the guide for the same length; very thick or coarse hair needs slightly more).
  3. Distribute Through Mid-Lengths and Ends — Apply the dispensed serum to the palms of both hands and rub together briefly to distribute evenly across both palms — then work through the mid-lengths and ends of the hair, running fingers through from mid-shaft to tip — avoid applying directly to the roots and scalp area: the scalp produces its own sebum and adding serum at the root zone creates buildup and a visually oily root appearance that most users do not want — if your hair is very dry at the roots, a minimal amount may be worked into the lower root zone, but keep the primary application focused on the mid-lengths and ends where the hair is oldest and most depleted of natural lipids.
  4. Comb Through and Style — After distributing through the hair, use a wide-tooth comb or a detangling brush to distribute the serum evenly through each strand and detangle any knots — the serum’s slip reduces the mechanical friction during combing, making this step significantly easier than combing through untreated wet or tangled hair — then proceed to air-dry or use your heat tool of choice — no rinse required — this is a leave-in treatment and is designed to remain in the hair after styling.
  5. Repeat at Each Wash Session or Dry-Hair Refresh as Needed — The serum can be used daily for dry-hair refresh applications — for wet-hair applications, apply at every wash session before drying — the non-greasy, easily absorbed formula does not create buildup with daily use and does not require a clarifying shampoo cycle to remove — if you notice the hair feeling heavy after several days of application, reduce the amount dispensed by half rather than skipping the application entirely.
🧸Short HairChin-length & shorter
Peanut-size amount
~0.5ml per session
💼Medium HairShoulder length
Almond-size amount
~0.8ml per session
🍒Long HairMid-back length
Cherry-size amount
~1.2ml per session
💡 Dosage Tips:
— Fine hair: use half the guide amount — fine strands are more susceptible to being weighed down by product
— Thick or coarse hair: increase by 20–30% above the guide if ends still feel dry after application
— Dry-hair touch-up: use approximately half the wet-hair amount — dry hair absorbs serum faster and less is needed to achieve the frizz-control benefit
— Heat styling: use the full wet-hair guide amount as the thermal protection requires full coverage of the hair shaft surface
Clean Formula

🚫 Paraben-Free. Sulfate-Free. Cruelty-Free. Dermatologically Tested. 100% Recyclable.

🚫
Paraben & Sulfate FreeParabens are synthetic preservatives linked to endocrine disruption concerns; sulfates are detergent surfactants that strip the hair’s natural oils — this serum contains neither — the formula is preserved without parabens and is free from sulfate surfactants that would counter the hydration benefit in a leave-in treatment
🐰
Cruelty-FreeNo animal testing at any stage of formula development or ingredient sourcing — cruelty-free certification confirms that neither the finished product nor its individual ingredient components are tested on animals
🔬
Dermatologically TestedThe formula has been tested under dermatological supervision for skin and scalp compatibility — suitable for use on sensitive scalps as a topical leave-in treatment — the non-greasy, rapidly absorbed formula does not leave a residue that would irritate sensitive scalp skin
♻️
100% Recyclable PackagingThe bottle, pump cap, carton box, and all printed materials are made from 100% recyclable materials — also free from paraffins (petroleum-derived waxes), mineral oil (petroleum derivative), and DEA (diethanolamine, a pH-adjusting compound with safety concerns) — a comprehensive exclusion list for a formula that competes on ingredient quality rather than synthetic cost-cutting
Specifications

Product Details

Feature Detail
Brand Nutra Harmony
Product Hydrating Hair Serum – Leave-In Conditioner
Volume 5 OZ / 150 ML
Key Actives Keratin · Argan Oil · Rosemary Oil · Wheat Protein
Supporting Actives Biotin · Castor Oil · Vitamins B & E
Benefits Nourishing · Hydrating · Smoothing · Repairing · Defrizzing · Protecting
Usage Modes On Wet Hair · On Dry Hair · Heat Styling Base
Heat Protection Blow-drying · Hair ironing · UV exposure
Formula Non-greasy · Easily absorbed · Soft floral scent · Leave-in (no rinse)
Free From Paraffins · Parabens · Sulfates · Mineral Oil · DEA · Animal Testing
Hair Types All hair types · Dry · Frizzy · Tangled · Colored · Curly · Damaged
Packaging 100% recyclable · Bottle, cap, carton, printed materials
Testing Dermatologically tested
Best For Daily leave-in care · Heat protection · Frizz control · Repair · Color-treated hair
FAQ

Common Questions, Answered

Can I use this on color-treated hair?

Yes — the formula is specifically listed as suitable for colored hair. The paraben-free, sulfate-free formula is important for color-treated hair because sulfates are the primary cause of color fade in wash routines — a sulfate-free leave-in treatment does not contribute to color stripping and the moisturizing and sealing effects of the keratin and oil actives actually help maintain color vibrancy by keeping the cuticle closed and reducing the porosity through which color molecules escape during washing. Apply as a leave-in after washing with a sulfate-free shampoo and conditioner for the best color-longevity routine.

Will this make my hair greasy?

The non-greasy formula and rapidly absorbed properties are the result of using lightweight carrier oils (Argan Oil) and water-soluble actives (keratin peptides, wheat protein, panthenol) rather than heavy silicones or mineral oil — the most common reason this type of serum causes a greasy appearance is using too much product — follow the hair-length dosage guide and apply to mid-lengths and ends only, avoiding the scalp and root zone — if you have fine hair, start with half the guide amount and increase only if you find the ends still feel dry after application.

Is this a rinse-out or leave-in conditioner?

This is a leave-in treatment — do not rinse out after application — it is designed to remain in the hair after styling and provides its benefits (hydration, frizz control, heat protection) throughout the day. It is not a substitute for a rinse-out conditioner used in the shower, but it can be used in addition to one for enhanced hydration and repair on very dry or damaged hair — apply after your rinse-out conditioner and towel-drying, before heat styling or air-drying.

Can I use this every day?

Yes — the formula is designed for daily use — the non-greasy, easily absorbed formula does not build up with daily application when used in the correct amount for your hair length and density. If your hair is only minimally dry or frizzy, you can also use it every other day as a preventative treatment rather than a daily corrective one. The 150ml size provides approximately 125–300 daily applications depending on hair length, so a single bottle provides 4–6 months of daily use for most hair lengths.

Is it safe for children or sensitive scalps?

The formula is dermatologically tested and free from parabens, sulfates, mineral oil, DEA, and paraffins, which are the ingredient categories most commonly associated with scalp sensitivity reactions. For children, we recommend consulting a pediatric dermatologist before introducing any hair treatment product. For adults with sensitive scalps, the formula’s clean ingredient profile and the dermatological testing make it a suitable option — apply to the hair shaft only, avoiding direct scalp contact, if you have a history of scalp sensitivity reactions to leave-in hair treatments.

Customer Reviews

My Frizz Is Gone After 3 Days. Replaced Four Products with One Bottle.

★★★★★
Dana R. Miami, FL

“I live in South Florida where the humidity is 80%+ for six months of the year and frizz has been my entire hair relationship since I was twelve. I’ve tried everything: the drugstore serums that make my hair oily by noon, the salon keratin treatments that cost $250 and last eight weeks, the expensive Moroccan oil that smells incredible but does nothing for actual frizz. This serum is the first drugstore-price product that has actually worked on my specific frizz type, which is the humidity-driven flyaway frizz that keratin doesn’t always fix. I apply it on damp hair after washing, comb through, air-dry, and my hair is smooth and shiny with no flyaways until the next wash. I’m on my third bottle in four months.”

★★★★★
Samantha L. New York, NY

“I color my hair every 6 weeks and use a flat iron 5 days a week — the combination has produced the most damaged, dry, split-end-covered hair I’ve ever had. My hairdresser told me I needed to stop using heat or start doing protein treatments every week — I compromised and started using this serum as a heat protectant every morning before the flat iron. Three months later: my ends are significantly less split, my hair feels thicker and more elastic, and my color is lasting longer between appointments — my colorist actually commented on the improvement without me saying anything. The heat protection is real. The repair benefit is real. This is now a permanent part of my routine.”

★★★★★
Priya M. Houston, TX

“I have 3B curly hair and finding a leave-in that hydrates without defining the curl in a crunchy, rigid way has been the recurring challenge of my haircare life. This serum hydrates, controls frizz, and adds shine without turning my curls into a cast. I use an almond-size amount on soaking-wet hair after washing, scrunch from ends up, then air-dry. The result is soft, defined, bouncy curls with no frizz and no crunch. I’ve recommended this to my entire natural hair community because the clean formula (no sulfates, no parabens) is also compatible with curly girl method routines, which rules out most commercial leave-in serums that contain silicones.”

Our Promise

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🌿6 Benefits in 1Complete hair care
🔥Heat ProtectionBlow dry, iron & UV
🚫Clean FormulaParaben & sulfate free
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↩️Easy ReturnsHassle-Free Policy
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Leave-in treatment · Do not rinse out · Apply to mid-lengths and ends · Avoid direct eye contact · Keep out of reach of children · External use only · Dermatologically tested.

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