Kérastase Nutritive Nutri-Supplement Scalp Serum is a moisturizing leave-on for a dry scalp, distinct from the Nutritive 8H Magic Night Serum used on hair lengths. The official page archived September 30, 2026 describes a milky, non-greasy fluid with niacinamide and glycerin and reports an immediate scalp-moisture result. That hydration evidence should not be rewritten as a measured increase in hair density.
Identify the Scalp Version
The official Nutri-Supplement page names the 90ml scalp serum. Its dry-scalp application separates it from other Nutritive products, including length conditioners, masks and overnight hair serums.
The source used here is a dated official snapshot checked September 30. Confirm the current package and regional formula before buying; this guide does not claim that all later stock or every regional listing is unchanged.
Understand the Immediate Moisture Claim
The main official description reports up to 23% more scalp moisture immediately after application, attributed to a clinical instrumental test. That is a hydration endpoint at a stated time, not a percentage of participants or a measured increase in hair growth.
The same archived page's FAQ uses the phrase hair moisture for a similar figure. This wording inconsistency should stay visible. The clearest main claim is the scalp-moisture statement; the archive does not justify inventing an additional independent hair-hydration study.
When the goal is dry-scalp moisture, the dry-scalp serum comparison helps distinguish lighter hydration, richer conditioning and symptoms that need assessment.
Swipe the table sideways to compare all columns.
| Decision | Documented detail | Purchase implication |
|---|---|---|
| Moisture | Up to23%immediately;instrumental claim | Not hair density |
| Perception | 31people with dry scalp,1week | Separate from instrumental test |
| Use | 2–4doses,dry/damp,leave in | Dose volume not guessed |
Keep the Consumer Results Separate
The page also reports that 100% agreed the product was not greasy on the scalp, 89% were satisfied and 86% said it nourished the scalp. These results come from 31 men and women with dry scalp after one week of use.
A consumer agreement rate is different from an instrumental moisture change. Do not combine them into a claim of 100% effectiveness or suggest that every user will experience the same finish.
Read the Full Formula beyond Niacinamide
The archived list includes water, glycerin, mineral oil, amodimethicone, conditioning agents, panthenol, niacinamide and fragrance components. The brand also describes a fatty-acid and vitamin blend and anti-dryness polymers.
Niacinamide is a relevant ingredient, but its percentage is not established here. A milky water-based formula may contain oils and silicones; water-based does not mean oil-free or silicone-free.
For the separate everyday-care choice, review the 30ml Lightweight Scalp Serum with Ginger.
Compare Moisturizing Formats by Their Own Evidence
The GinGrowth options provide ordinary moisture, without claiming Kérastase’s instrumental result. GinGrowth sells the two products below.
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| Detail | 30ml Lightweight Scalp Serum with Ginger | 40ml Ginger Hair Tonic for Scalp & Roots |
|---|---|---|
| Format | Water-based dropper essence | Water-based dropper tonic |
| Ingredient highlights | Aqua, glycerin, ginger root oil, Polygonum multiflorum extract and hydroxyethylcellulose in the ingredient graphic. | Ginger extract, glycerin, sodium PCA and panthenol, alongside aqua, in the product artwork. |
| Application | After washing and drying, apply a small amount to the scalp, massage gently and leave in. The product guide describes daily use. | Part hair, apply a small amount, massage gently for 2–3 minutes and leave on. Follow the current bottle for frequency. |
| Reason to compare | Choose for a light moisturizing step and precise placement along a part. | Choose for a larger dropper format with humectant and conditioning ingredient highlights. |
View 30ml Lightweight Scalp Serum with Ginger or compare 40ml Ginger Hair Tonic for Scalp & Roots. Review the current product page for price and package details.
The essence contains ginger root oil within a water-based formula. That is different from buying a bottle of pure essential oil. Glycerin provides a concrete moisturizing ingredient to compare, while the dropper helps direct a small amount to the scalp. Use the finish on your own hair as the practical test: controlled placement matters more than saturating the roots or spreading scalp care through the lengths.
Glycerin and sodium PCA are moisture-binding ingredients, while panthenol is used for conditioning. The highlighted ingredient graphic is not a percentage breakdown. The word tonic describes this product choice; it does not establish a stronger concentration than the smaller essence. Compare the ingredients you prefer and whether direct dropper placement feels convenient in your routine.
Follow the Documented Application
The official directions say to apply section by section to dry or damp scalp, use two to four doses according to hair thickness, massage to distribute and leave in. Blow-drying is allowed, and use is described as often as needed.
The word dose is not converted here into an invented milliliter amount. Use the marked applicator and the current package's definition. Do not borrow a four-dose daily schedule from Genesis simply because both are Kérastase serums.
For that scalp product’s routine, the Nutri-Supplement application guide explains the stated doses without inventing a milliliter conversion.
Compare Moisture on Equal Terms
GinGrowth's essence and tonic below are separate moisturizing options sold by GinGrowth. They offer different formula highlights and bottle sizes, without a claim to reproduce the Nutri-Supplement instrumental or consumer results.
If a milky finish, a specific ingredient system or the documented Kérastase study matters most, keep that requirement explicit. If the task is ordinary scalp moisture with a dropper, compare the current product instructions and ingredients rather than assuming the cheaper or larger bottle has equal evidence.
Decide Whether Dryness Is the Actual Problem
A tight or dry feel may make a moisturizing step useful, but flakes, itch and inflammation can have several causes. The AAD describes reasons for scalp itch that require different responses.
A serum marketed for dry scalp should not automatically replace a medicated dandruff product or treatment for another diagnosed condition. Keep the relevant instructions intact.
Interpret the Growth-Environment Language
The brand describes creating a healthier basis for new hair growth. That is different from reporting a controlled hair-count trial showing regrowth from this formula. The documented numerical endpoints here concern moisture and consumer perceptions.
For progressing thinning, the AAD's diagnosis-led treatment guidance is more useful than treating a dry-scalp moisturizer as a universal hair-loss solution.
Plan a Practical Moisture Review
Record comfort, residue and how the product fits your wash and styling routine. Compare similar conditions instead of judging one product on a freshly washed day and another after several layers of styling products.
Stop if irritation worsens. A non-greasy study result or a premium positioning does not guarantee tolerance for every scalp. Save the package information if you need help reviewing a reaction or a formula mismatch.
Frequently Asked Questions
Is this the 8H Magic Night Serum?
No. This guide concerns Nutri-Supplement Scalp Serum and its scalp-specific directions.
Does 23% mean 23% more hair?
No. The main archived claim concerns immediate scalp moisture.
Is the formula silicone-free?
The archived ingredient list contains amodimethicone. Verify the actual package if this is a purchase requirement.
Make the Next Step a Formula Check
Choose Nutri-Supplement for its documented dry-scalp moisturizing role if that matches your need. Confirm the current regional package and application details, especially where online wording differs. For another ordinary moisturizer, use the separate GinGrowth comparison; for continuing loss, obtain a treatment decision matched to the cause.
Choose the care role and formula that match your routine.
Sources and Product Information
- Kérastase Nutri-Supplement: dated official product information — Official snapshot checked September 30, 2026; current regional package should be verified. Main scalp-moisture and FAQ hair-moisture wording conflict is disclosed.
- AAD: Hair loss diagnosis and treatment — Guidance checked October 1, 2026; not a trial of the cosmetics compared here.
- AAD: Causes of scalp itch — Guidance checked October 1, 2026.
GinGrowth product details were checked October 1, 2026. This guide compares published information and current product specifications; it does not report a GinGrowth clinical trial or personal use test.