INCI Guide (III): Ingredient Nomenclature and Patterns

In Part I, we learned what INCI is and how to interpret it. In Part II, we reviewed ingredient groups by function. This third part goes a step further: recognizing ingredients by name, without having to look them up one by one. There are patterns in INCI nomenclature that, once known, allow you to identify an ingredient's type just by reading its name.

It's not foolproof; there are exceptions, but it covers the vast majority of what you'll find on a label.

Aqua: always water, always at the beginning

It's not abundant in our catalog, but it is in conventional cosmetics, especially because it's the base in liquid formats. It's the simplest of all. Aqua is water, and in most creams, aqueous serums, and cleansing products, it usually appears as the first ingredient because it's the base of the formula. There's nothing more to know about this, except that its presence implies the product needs preservatives to avoid contamination.

If a product doesn't have Aqua in the INCI, it's anhydrous (water-free): oils, butters, solid bars, balms. These need much less preservative or none at all.

Oil, Butter, Wax: vegetable fats

Any ingredient ending in Oil is an oil. Seed Oil refers to oil extracted from the soft seed of the fruit. Kernel Oil is oil from the soft seed protected by a hard stone or shell:

If preceded by a botanical name in Latin, it is a vegetable oil:

• Simmondsia Chinensis Seed Oil: jojoba seed oil.
• Rosa Moschata Seed Oil: rosehip seed oil.
• Argania Spinosa Kernel Oil: argan kernel oil.

If the name is more generic or chemical, it may be a mineral or synthetic oil: Mineral Oil, Paraffinum Liquidum (liquid paraffin). You won't find these in our catalog.

Butter indicates butter, and in natural cosmetics, it is always of plant origin:

• Butyrospermum Parkii Butter: shea butter.
• Theobroma Cacao Seed Butter: cocoa seed butter.

Wax or Cera are waxes. They function as occlusives and texture agents in sticks and balms. All are of plant origin, except beeswax, which comes from beekeeping.

The INCI mixes Latin and English depending on the registration period: older names remained in Latin (Cera), newer ones are written in English (Wax). Same ingredient, different convention.

• Cera Alba: beeswax.
• Candelilla Cera: candelilla wax.
• Carnauba Wax: carnauba wax.

Botanical names in Latin: certified plant origin

Some botanical names you'll recognize immediately: Lavandula Angustifolia is lavender, Rosa Damascena is Damask rose, Olea Europaea is olive. Others require a bit more practice, but the logic and pattern are always the same: genus + species + plant part + extract form.

• Camellia Sinensis Leaf Extract: green tea leaf extract.
• Punica Granatum Fruit Extract: pomegranate fruit extract.
• Aloe Barbadensis Leaf Juice: aloe vera leaf juice.

When you see two Latin words followed by Extract, Oil, Powder, Juice, or similar, you're looking at a plant-derived ingredient. It's one of the easiest INCI readings once you know the pattern.

The -ols: the suffix that can be confusing

The suffix -ol indicates an alcohol, but here there's an important distinction worth knowing.

Fatty alcohols: long-chain, solid at room temperature, emollients and stabilizers. They don't dry out or irritate; on the contrary, they soften. Cetyl Alcohol, Cetearyl Alcohol, Behenyl Alcohol, Stearyl Alcohol. They are very common in creams and conditioners to provide a creamy texture. Their name might sound like "alcohol" and cause alarm, but their behavior is completely different from volatile alcohol.

Volatile alcohol: Alcohol Denat., Ethanol, Isopropyl Alcohol. These evaporate quickly, can dry out and disrupt the skin barrier, especially in sensitive skin. In low concentrations and well-formulated products, they are not necessarily problematic, but it's worth considering if they appear among the first ingredients.

Actives with -ol: some active ingredients also end in -ol due to their chemical structure: Retinol (vitamin A), Panthenol (provitamin B5), Tocopherol (vitamin E), Bisabolol (chamomile soothing agent). They have nothing to do with the previous alcohols, even though they share the same ending.

The -ate and -ite: salts, esters and preservatives

The suffix -ate indicates a salt or an ester. This is a very broad group that includes ingredients with very different functions.

Preservatives: Sodium Benzoate, Potassium Sorbate, Sodium Dehydroacetate. These are among the most commonly used preservatives in natural cosmetics, generally well tolerated.

Emulsifiers and stabilizers: Glyceryl Stearate, Cetearyl Glucoside (coconut-derived emulsifier), Sorbitan Olivate (emulsifier and surfactant derived from olive oil and sorbitol). Natural ones like these allow water and oil to coexist in a cream without separating, are biocompatible with the skin, retain moisture, and strengthen the natural lipid barrier.

Esters of vegetable oils: Esters are chemical compounds formed when an acid combines with an alcohol, losing a water molecule. In the world of cosmetics and nature, they are the components responsible for providing good scent, softness, and texture to a wide variety of products. Caprylic/Capric Triglyceride (light fraction of coconut oil, very emollient), Isopropyl Myristate (common synthetic emollient in conventional cosmetics).

The suffix -ite follows the same logic but derives from different acids: where -ate comes from acids ending in -ic, -ite comes from acids ending in -ous. In cosmetic practice, the distinction does not change anything functional: Sodium Sulfite, Magnesium Ascorbyl Phosphite. Same reading criterion, different chemical family.

The -sulfate and -sulfonate: surfactants, but not all are equal

As we saw in Part II, surfactants are the basis of cleansing products. Those with -sulfate in the name are the best known, but not all have the same profile.

The aggressive ones: Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES) are the most common in mass-market products: shampoos, shower gels, conventional toothpastes. They clean effectively but excessively strip natural lipids, alter pH, and can irritate with continued use. If they appear among the first ingredients in a cleansing product, the formula is aggressive.

The mild ones: not all names with sulf- are problematic. Sodium Lauryl Sulfoacetate (SLSA) is considerably milder than SLS despite the similar name. Disodium Lauryl Sulfosuccinate also has a much more skin-friendly profile and is common in products for sensitive skin or children.

Coconut derivatives: Sodium Cocoyl Isethionate (SCI), the base of many syndets, is technically a sulfonic ester rather than a sulfate, but is mentioned here because its name can cause confusion. Its behavior is completely different: mild, pH-balanced, non-drying. Coconut surfactants in general, Coco-Glucoside, Sodium Cocoamphoacetate, are the natural and respectful alternative to conventional sulfates.

The practical rule: SLS and SLES are worth specifically avoiding. The rest require more context.

The -siloxane and -cone: silicones

Easy to identify. Any ingredient ending in -cone, -conol, -siloxane or -silane is a silicone (Dimethicone, Cyclopentasiloxane, Cyclohexasiloxane, Phenyl Trimethicone).

Silicones are very effective emollients in functional terms: they give an immediate silky texture, soften and add shine. The problem is that they form an impermeable occlusive film on the skin or hair without providing real nourishment. They create a "makeup effect" that hides dehydration and, in addition, insoluble varieties (such as Dimethicone) require aggressive cleansers to remove them. Due to their high environmental impact, many of them (such as cyclic or volatile ones) are under strict prohibitions in the European Union as they are not biodegradable.

In natural cosmetics, they are absent, replaced by vegetable oils and waxes that provide a similar effect with real benefit for the skin.

The -paraben: preservatives under scrutiny

The suffix -paraben makes them immediately recognizable: Methylparaben, Ethylparaben, Propylparaben, Butylparaben, Isobutylparaben.

They were the standard for preservation in cosmetics for decades due to their efficacy and stability. Their controversy arises from studies that detected parabens in breast tissue and their weak estrogenic activity, which placed them in the debate on endocrine disruptors.

Scientific evidence remains debated. The SCCS (Scientific Committee on Consumer Safety of the European Union) considers short-chain parabens (Methyl- and Ethyl-) safe at usual concentrations. However, authorities completely banned varieties such as Isobutylparaben and strictly restricted Butylparaben and Propylparaben.

Many brands have removed them as a preventive measure. Their presence in an INCI is not automatically illegal, but it is relevant information for those who wish to avoid them.

CI + number: colorants, natural and synthetic

The prefix CI (Color Index) followed by a five-digit number identifies a colorant approved for cosmetic use. The system does not distinguish origin: under this prefix coexist mineral pigments, natural colorants, and synthetic petroleum derivatives.

• Mineral pigments: CI 77491, CI 77492, CI 77499 are iron oxides that give reddish, yellow, and black tones in natural cosmetics. CI 77891 is titanium dioxide (used to give white color and as a sunscreen, although today it is highly regulated and restricted in powder products). CI 77007 is ultramarine blue. All are of mineral origin and common in natural cosmetics.
• Of animal origin: CI 75470 is carmine, obtained from cochineal. It is a natural dye but it is not vegan, a key fact for those looking for cruelty-free cosmetics.
• Synthetics: CI 42090 (blue), CI 19140 (yellow tartrazine) or CI 16035 (red). These are petroleum derivatives and are the most questioned for their potential allergenic effect on sensitive skin.

Seeing the CI acronym in an INCI does not automatically imply a synthetic ingredient. To know, you have to know the specific number or search to find out what it is. In any case, colorants have no function on the skin: they are there for aesthetic reasons of the product, not for the benefit of the user.

Fragrance allergens: those that must be declared

Within the term Parfum or Fragrance there can be dozens of different compounds. European regulation requires individual declaration of fragrance allergens when they exceed certain concentrations: 0.001% in rinse-off products and 0.01% in leave-on products.

The most common ones you'll see declared: Limonene (citrus), Linalool (lavender, other florals), Citral (lemon, verbena), Geraniol (rose, geranium), Eugenol (clove, cinnamon), Cinnamal (cinnamon), Benzyl Alcohol, Coumarin, Citronellol.

Some come from natural essential oils, others are synthetic. Their presence does not mean the product is bad or poorly formulated: it means it contains fragrance compounds that can sensitize very reactive skin or skin with a history of allergies. For those with sensitive skin, reviewing this part of the INCI is especially useful.

A completely fragrance-free product will not have any of these terms or the word Parfum. It is the safest option for reactive skin.

For most people, however, sensory experience carries some weight in their personal care routines. If you don't have reactive skin or a history of allergies, there's no reason to avoid them.

Actives: heterogeneous by nature

Actives are the most diverse group in nomenclature because they come from very different origins and do not follow a single pattern. However, there are recognizable subgroups.

Compound's proper name in English: They are recognized because they are the direct name of the compound without systematic suffixes. With some practice, we will easily recognize them. Some examples:

• Niacinamide, Retinol, Caffeine, Bakuchiol, Astaxanthin.

Acids: many exfoliating, renewing, or moisturizing active ingredients have Acid in their name. Easy to identify. Examples:

• Lactic Acid (lactic acid), Hyaluronic Acid (hyaluronic acid), Ascorbic Acid (vitamin C), Glycolic Acid (glycolic acid), Azelaic Acid (azelaic acid).

Vitamins by their chemical name: they don't appear as "vitamin X" but by their technical name:

• Tocopherol or Tocopheryl Acetate is vitamin E. Ascorbic Acid is vitamin C. Niacinamide is vitamin B3. Retinol is vitamin A. Panthenol is provitamin B5.

Active botanical extracts: follow the Latin botanical name pattern we saw earlier:

• Camellia Sinensis Leaf Extract provides antioxidants from green tea. Punica Granatum Extract provides polyphenols from pomegranate. Centella Asiatica Extract provides madecassoside and asiaticoside, with soothing and repairing action.

Peptides: have Peptide in the name or the prefix Palmitoyl:

• Palmitoyl Tripeptide-1, Acetyl Hexapeptide-3, Copper Tripeptide-1. These are anti-aging active ingredients with action on collagen and firmness, common in high-end serums.

As we said at the beginning of this guide, the difference between an effective active ingredient and a decorative one is not in the name but in the concentration. A botanical extract at 0.001% in the list barely does anything. The order in the INCI is still the key to evaluating whether an active ingredient is in a relevant amount or simply to justify a claim on the packaging.

A summary to keep in mind

With these keys, you can read any INCI with good judgment without having to look up every ingredient:

• Aqua at the beginning: aqueous base, needs preservatives.
• Oil/Extract/Butter with a botanical name in Latin before it: plant ingredient.
• -ol: can be fatty alcohol (good), volatile alcohol (with caution) or active (depends on which one).
• -ate/-ite: salt or ester, variable function.
• SLS/SLES: aggressive surfactants.
• -cone/-siloxane: silicones, we do not recommend them.
• -paraben: preservative under debate. Our advice: avoid it.
• CI + number: colorant, variable origin.
• Declared allergens (Limonene, Linalool...): fragrance components to consider for reactive skin.
• Actives: proper name in English without a systematic suffix: probably an active ingredient.

Reading the INCI and understanding the ingredients will help us know what we are putting on our skin, hair, or in our mouth, regardless of what is written on the front of the packaging. The front sells. The INCI informs.

With the three parts of this guide, you have the tools to make informed decisions: understand the logic of the ingredient list, recognize ingredient groups by their function, and identify them by their name. With practice, patterns become automatic, and reading becomes fast.

The goal is not to generate distrust or turn every purchase into an examination. It's to give you context to choose better, to access real information, and not just rely on marketing claims. That's what we try to do at CUIDA-T with every product in our catalog: ensure that the INCI list supports what the label says, without unnecessary fillers.

To learn more about some of the mentioned ingredients, you will find them in our ingredient glossary or the Learn More fact sheets.

Missed the beginning? Read INCI Guide Part I and INCI Guide Part II.