Reviewed by Tara Sullivan · Updated October 2026 · 10 min read
For fine, flat hair, the best Redken shampoo is still Volume Injection. For thinning hair, Redken now has a separate line, Acidic Grow Full System, and Redken itself says it does not grow hair. Both are useful, as long as you know which problem each one solves.
Below is the current Redken range sorted for fine and thinning hair, with sizes, prices and ingredients read on Redken's own site, plus what was renamed or discontinued and a routine that will not weigh fine hair down.
a volumizing shampoo bottle, a mousse can and a round brush on a pale bathroom shelf, soft daylight
This guide is independent and unpaid. Every size, price and ingredient below was checked on Redken's own product pages in October 2026, and we link to the brand directly.
From the editor
Redken is a salon brand most fine-haired clients have already met, usually through a stylist's blow-dry. The trouble starts at home, when the bonding conditioner from a damage line goes on fine roots.
The rule for fine hair is simple: wash with the volume line, keep the rich conditioners off your roots, and choose one styler, not three.
MH
— Megan Holloway, Editor-in-Chief
The short verdict
Fine, flat hair: Volume Injection Shampoo and Conditioner, plus Root Lifter or Stay High Mousse at the root. Thinning hair that breaks when you brush it: the Acidic Grow Full System shampoo and serum.
Skip for fine hair: the Acidic Bonding Concentrate conditioner, which Redken calls "ultra-rich" and which lists two silicones near the top. It is built for heavily damaged hair, not for lift.
The best Redken shampoo and conditioner for fine hair
Volume Injection is Redken's fine-hair wash, and it is still sold under that name. The shampoo uses what Redken calls Filloxane, a silane-based thickening ingredient, plus fixative polymers that leave a little grip on the strand.
It is a strong cleanser. Both sodium laureth sulfate and sodium lauryl sulfate are high in the list, which is good for oily roots and less good for dry, colour-treated ends.
Redken Volume Injection Shampoo bottle, product packshot on white
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Best Redken shampoo for fine hair: Redken Volume Injection Shampoo
Redken says it gives "instant lift at the root and enhanced body", and it lists it for "flat hair prone to oiliness". There is no dimethicone and no oil in the formula, so nothing coats the root.
Sizes: 10.1 fl oz for $31, 33.8 fl oz for $58. Honest limitation: it is not sulfate-free, and it contains the preservatives MCI/MI, a known skin sensitiser. If your colour fades fast or your scalp is reactive, alternate it with a gentler wash.
Redken Volume Injection Conditioner bottle, product packshot on white
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Best Redken conditioner for fine hair: Redken Volume Injection Conditioner
A light, sulfate-free cream that Redken contrasts with "thicker, cream formulations that weigh down". The ingredient list has no silicones or oils, which is rare for a salon conditioner.
Sizes: 10.1 fl oz for $31, 33.8 fl oz for $58. Honest limitation: it gives little slip, so long or bleached fine hair may still tangle. Use it from the ears down.
Redken Acidic Grow Full System Densifying Shampoo bottle, product packshot on white
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Best Redken shampoo for thinning hair: Acidic Grow Full System Densifying Shampoo
New in 2026. It pairs azelaic acid, caffeine and prebiotics with a sulfate base, and Redken says the full four-step system makes hair "2X stronger" with "2X less breakage" from brushing.
Sizes: 10.1 fl oz for $37, 33.8 fl oz for $71. Honest limitation: those claims are for the whole system against a non-conditioning shampoo, with no sample size or study length published. The caffeine sits low in a rinse-off formula.
Redken Acidic Grow Full System Scalp and Hair Serum dropper bottle, product packshot on white
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For a thinning part: Acidic Grow Full System Scalp & Hair Serum
A leave-on scalp serum with caffeine, azelaic acid, glycerin and hyaluronic acid, and no silicones or heavy oils. Of the four Acidic Grow products, it is the only one that stays on the scalp long enough for its actives to matter.
Sizes: 1.5 fl oz for $26, 3.4 fl oz for $48. Honest limitation: it is a cosmetic, not a drug. It contains no minoxidil, and Redken's FAQ answers "Is it for hair loss/thinning?" with: "No, it is not growing new hair."
Redken confirms that Root Lifter and Guts 10 "contain exactly the same formula"; only the name and pack changed. It sprays on as a light foam aimed at the roots of damp hair, with medium control.
Sizes: 2.1 oz for $16, 10.58 oz for $30. Honest limitation: it contains amodimethicone, a silicone, mid-list. Too much on an oily scalp leaves roots piecey by day two.
Redken Stay High gel-to-mousse can, product packshot on white
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Best mousse for fine hair: Redken Stay High Mousse
Back in 2026 after being discontinued in 2022, with the formula "unchanged from the original". Redken lists it for "normal to fine, thin or flat hair seeking volume and firm hold", and it is silicone-free.
Size: 5.3 fl oz for $32. Honest limitation: firm hold can feel stiff or tacky on very fine hair, so start with a golf-ball amount. If you want a softer result, Redken's Full Volume Mousse (10.6 oz, $30) bodies the lengths more than the root.
Redken Volume Maximizer thickening spray bottle, product packshot on white
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Best thickening spray: Redken Volume Maximizer
A weightless spray of volumizing polymers and ceramides that is sulfate-free and silicone-free. It coats each strand with a light film, which makes fine hair look thicker until the next wash.
Size: 8.5 fl oz for $32. Honest limitation: alcohol is the second ingredient, so overuse feels crunchy. Redken's newer Acidic Grow Instant Densifying Spray ($40) uses an almost identical base.
For hair that looks thinner because it breaks, it can help. The Acidic Grow line is built to reduce breakage from brushing and to make hair look fuller, and Redken's footnotes say every claim was measured using the full four-product system.
It does not treat thinning from the follicle. Redken's own FAQ says so, and none of the products contains a drug. If your part is widening, start with fine hair or thinning? and see thinning hair treatment for what does work.
One claim is worth reading closely: "91% of GLP-1 users agreed hair feels thicker". That is a consumer self-assessment, not a measurement. If your shedding began on a weight-loss drug, weight loss and hair shedding explains why it usually settles on its own.
What happened to Cerafill, Guts 10 and Full Frame?
Cerafill, Redken's old thinning line (Retaliate, Maximize, Defy), is no longer sold on redken.com; searching for it redirects to Redken's discontinued-products page. Acidic Grow is its practical replacement.
Guts 10 is now Root Lifter, same formula. Full Frame 07 appears to live on as Full Volume Mousse; Redken's page still links it to a "Full Frame 07 routine", though it does not say so outright.
Redken Acidic Bonding Concentrate and fine hair
ABC is excellent for bleached, broken hair, and it is the Redken line most likely to flatten fine hair. The conditioner lists dimethicone and an amodimethicone among its first six ingredients, plus candelilla wax.
We could not find a fine-hair version of ABC on Redken's site in October 2026. If your fine hair is heavily lightened, use the ABC shampoo and keep the conditioner to the last few inches. Our best bond builder for fine hair compares lighter options.
A simple Redken routine for fine hair
Wash with Volume Injection Shampoo, and condition from the ears down with Volume Injection Conditioner. On towel-dried hair, spray Root Lifter at the part and crown, or work in a small amount of Stay High.
Blow-dry upside down until mostly dry, then finish with a round brush; how to blow-dry fine hair has the method. If your colour fades quickly, swap in a sulfate-free shampoo every other wash.
FAQ
Redken Volume Injection Shampoo. It is designed for fine, flat hair, contains no silicones or oils, and leaves a light polymer grip for lift. It uses sulfates, so pair it with a gentler shampoo if your hair is colour-treated or dry at the ends.
The Acidic Grow Full System Densifying Shampoo, launched in 2026, is Redken’s shampoo for thin hair that breaks easily. It contains azelaic acid, caffeine and prebiotics. Redken says the system does not grow new hair; it reduces breakage so hair looks fuller.
Not in the US. Searching for Cerafill on redken.com redirects to the discontinued-products page, and Retaliate returns no results. The Acidic Grow Full System is Redken’s current line for thinning hair.
Yes. Redken says Root Lifter and Guts 10 contain exactly the same formula; the product was renamed and repackaged.
The shampoo can be, if your fine hair is bleached or damaged. The conditioner is rich, with silicones and wax high in the list, so on fine hair use it only on the ends. We found no fine-hair version of ABC on Redken’s site.
No. Redken’s own FAQ says it is not growing new hair. Its claims are about stronger hair, less breakage from brushing and a fuller look, measured using all four products together.
The conditioner is; the shampoo is not. Volume Injection Shampoo contains sodium laureth sulfate and sodium lauryl sulfate, which clean oily roots well but can fade colour.
Sizes, prices and ingredients were checked on Redken’s official site in October 2026; formulas and prices change, so check the label before you buy. This guide is independent; Redken did not see it or pay for it.
Images in this article are AI-generated illustrations, not photos of real clients or results. See our image policy.
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