Pro Clinical Age Defense Serum

In the US, ingredients above 1% are listed from most to least. Below 1% they can appear in any order. Each note keeps three things apart: what the ingredient generally does, its role in this type of product, and what its position can tell you.

• 1 Water · Aqua/Water/Eau
  General function

  The base of almost every rinse-off and cream hair product. It carries everything else and is normally the first ingredient on the label.

  Leading ingredient

  Listed in the first three ingredients, it is likely a structural part of this formula.

  • solvent
• 2 Alcohol Denat. · Alcohol Denat
  General function

  Fast-drying alcohol used to make sprays set quickly. In leave-on products it can leave hair feeling dry, especially in high position on the list.

  Leading ingredient

  Listed in the first three ingredients, it is likely a structural part of this formula.

  May suitFine or easily flattened hair

  Evaporates on contact, which is how a spray sets almost instantly and leaves no weight behind it.

  May not suitDry, coarse, or high-porosity hair

  Porous hair gives water up easily as it is; a fast-evaporating solvent high on the list accelerates that.

  May not suitVery dry or highly damaged hair

  It evaporates quickly and takes some water with it. On hair already short of moisture, a formula built on a lot of it can finish drier than it started.

  PubChem
  • drying alcohol
  • solvent
• 3 Glycerin
  General function

  Glycerin, also called glycerol, attracts moisture and mixes completely with water.

  Leading ingredient

  Listed in the first three ingredients, it is likely a structural part of this formula.

  May suitDry, coarse, or high-porosity hair

  High-porosity hair loses water fast; a humectant holds some of it in place for longer than the wash itself would.

  May suitVery dry or highly damaged hair

  Binds water into the outer layers of the strand, and water is what makes dry hair flexible again rather than brittle.

  DependsClimate-sensitive or frizz-prone hair

  Water moves both ways. Measured across concentrations, glycerin solutions give water up in some conditions and take it from the air in others. What it does for you depends on how much of it is there and on the air around it.

  Scientific Reports
  • humectant
• 4 Niacinamide
  General function

  Vitamin B3, used in scalp products for conditioning claims.

  Supporting ingredient

  Listed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.

  May suitFrizz-prone, damaged, or high-friction hair

  Deposits a lubricating layer that makes combing easier, which is most of what stops mechanical damage adding to frizz.

  PubChem
  • vitamin
  • conditioning agent
• 5 Butylene Glycol
  General function

  A light humectant and carrier that helps extracts dissolve.

  Supporting ingredient

  Listed in positions 4–8, it likely makes a meaningful contribution alongside the formula's main ingredients.

  May suitFine or easily flattened hair

  Light and water-binding rather than oily, so it adds less weight than oils or butters do.

  May suitVery dry or highly damaged hair

  A small water-binding solvent. It holds moisture and helps the rest of the formula spread evenly over the strand.

  DependsClimate-sensitive or frizz-prone hair

  A humectant follows the air: it holds water in humid conditions and can give it up in very dry ones. Climate decides what it does more than the label does.

  PubChem
  • humectant
  • solvent
• ▾Below about here, the order stops meaning much. These are usually used at 1% or less.
• 6 Fragrance · Parfum/Fragrance
  General function

  An undisclosed blend of scent ingredients. Regulations let it stay unlisted, so a fragrance-free product is the only way to be certain what is not in it.

  Estimated lower-concentration zone

  It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

  May not suitFragrance-sensitive routines

  Declared fragrance. On a fragrance-sensitive routine this is the line that decides it, wherever it sits on the label.

  • fragrance
  • declared fragrance
• 7 Xanthan Gum
  General function

  A fermented sugar gum that thickens water-based formulas and adds soft, natural hold.

  Estimated lower-concentration zone

  It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

  May suitCurls or waves needing flexible hold

  A polysaccharide film stays softer than a synthetic one as it dries, which is what leaves a curl defined but still able to move.

  May suitFrizz-prone, damaged, or high-friction hair

  A soft film binds neighbouring strands together, which is most of what helps flyaways lie down.

  May not suitMaximum-hold styling

  Gum films stay soft. A style that needs firm fixation usually wants a synthetic polymer doing the holding.

  • gum
  • thickener
  • film former
• 8 Alcohol Denat. · Alcohol
  General function

  Fast-drying alcohol used to make sprays set quickly. In leave-on products it can leave hair feeling dry, especially in high position on the list.

  Estimated lower-concentration zone

  It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

  May suitFine or easily flattened hair

  Evaporates on contact, which is how a spray sets almost instantly and leaves no weight behind it.

  PubChem
  • drying alcohol
  • solvent
• 9 Caffeine
  • active
• 10 PEG-40 Hydrogenated Castor Oil
  • solubilizer
  • emulsifier
• 11 Mentha Piperita (Peppermint) Oil · Mentha Piperita Oil
  General function

  Peppermint essential oil, used for scent and the cooling feeling on the scalp.

  Estimated lower-concentration zone

  It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

  May not suitFragrance-sensitive routines

  Essential oils are fragrance. Several carry constituents on the EU list of declared fragrance allergens, so a label with no fragrance line can still be a scented product.

  • botanical extract
  • essential oil
  • fragrance
• 12 Avena Strigosa Seed Extract
  • botanical extract
• 13 Ononis Spinosa Root Extract
• 14 Citric Acid
  General function

  Used to bring the product to a slightly acidic pH, which helps the cuticle lie flat. It is almost always near the end of the list.

  Estimated lower-concentration zone

  It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

  May suitBuild-up-sensitive routines

  Holds hard-water minerals in solution so they rinse away instead of depositing on the hair.

  May suitFrizz-prone, damaged, or high-friction hair

  The acid side of pH adjustment, and the reason it matters is measured: alkaline formulas raise the fibre's surface negative charge, increase friction between strands and lift the scales, while lower-pH ones do the reverse.

  May suitGray, silver, or brass-prone hair

  Where a warm cast comes from water minerals rather than from the hair itself, holding those metals in solution is what removes it.

  International Journal of Trichology
  • pH adjuster
  • hard-water chelator
• 15 Menthol
  General function

  Produces the cooling, tingling feeling on the scalp. The sensation is real; it is not evidence that anything else is happening.

  Estimated lower-concentration zone

  It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

  May not suitFragrance-sensitive routines

  Declared fragrance. On a fragrance-sensitive routine this is the line that decides it, wherever it sits on the label.

  PubChem
  • fragrance
  • active
• 16 Mentha Arvensis Leaf Oil
  General function

  Cornmint oil, used for a cooling sensation and mint scent.

  Estimated lower-concentration zone

  It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

  May not suitFragrance-sensitive routines

  Declared fragrance. On a fragrance-sensitive routine this is the line that decides it, wherever it sits on the label.

  • fragrance
  • botanical extract
• 17 Nasturtium Officinale Leaf/Stem Extract
• 18 Limonene
  General function

  A citrus-smelling fragrance component that EU rules require to be named separately because some people react to it.

  Estimated lower-concentration zone

  It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

  May not suitFragrance-sensitive routines

  One of the 26 scent components the EU requires to be named individually above a threshold. It is named because it is a known contact allergen, not because it is unusual.

  PubChem
  • fragrance
  • named fragrance allergen
• 19 Pinene
  General function

  A pine-scented component of essential oils, declared as part of the fragrance.

  Estimated lower-concentration zone

  It appears around or below the estimated 1% line, where label order no longer indicates relative amount; its role may be minor or technical.

  May not suitFragrance-sensitive routines

  Declared fragrance. On a fragrance-sensitive routine this is the line that decides it, wherever it sits on the label.

  • fragrance

What the whole list adds up to

• 6 fragrances
• 4 solvents
• 3 botanical extracts
• 2 drying alcohols
• 2 humectants
• 2 actives
• 1 vitamin
• 1 conditioning agent
• 1 declared fragrance
• 1 gum
• 1 thickener
• 1 film former
• 1 solubilizer
• 1 emulsifier

Ingredient list captured 2026-09-11. Formulas change, so check the package in your hand when an ingredient matters to you.