Your Guide to Reading The INCI List – Skin Rocks

Your Guide to Reading The INCI List

The first thing to know is that the INCI list is just that: a guide.

While nobody is expecting you to know exactly what every single ingredient does (unless you are a cosmetic scientist), learning how to decode the INCI list can help you avoid buying products that don't suit your skin or live up to their claims. Here’s what you need to know.

What does the INCI list mean?

To help improve the consistency of product labelling, a standardised system called the International Nomenclature of Cosmetics Ingredients (INCI, for short) was introduced in the 1970s. This outlines all of the ingredients that a product contains and is typically found on the back of the packaging or on the printed leaflet found within.

The INCI list doesn’t reveal the origin, how it was extracted, or produced, if it’s animal-derived, vegetable-derived, refined, unrefined, or lab synthesised.

Highest to lowest concentration

By law, beauty brands must list their ingredients in order of concentration, from highest to lowest. Once you get down to 1%, ingredients can be listed in any order.

An easy way to figure out when you’ve reached the ‘less-than-one-percent’ ingredients is to look for ‘phenoxyethanol’ or parabens, as they have a set limit of 1% in skincare formulations. 

1st ingredient: The Base

The first ingredient on an INCI is the base, acting as a solvent (delivery system) for other actives and carrying them into your skin to work their magic. The most common base is water (often labelled as aqua) or, for oil-based products, you will often see a plant oil such as jojoba or sweet almond.

Common ingredients and their functions: 

  • Key ingredients - These are the ingredients that have been added to the formula to make a potential change to the skin, and are usually the ‘actives’.

e.g. vitamin C, niacinamide, retinoids and alpha hydroxy acids (e.g. glycolic acid) 

  • Emulsifiers – Help keep the product stable and prevent it from separating 

e.g. polysorbates, laureth-4, and potassium cetyl sulfate. 

  • Silicones – Make a product smoother and easier to spread. Also often act as emollients, with skin conditioning benefits.

e.g. dimethicone, phenyl trimethicone, cyclopentasiloxane 

  • Solvents - Dissolve other ingredients.

e.g. aqua (water), alcohol denat., C10-13 isoalkane, butylene glycol  

  • Surfactants – Aid the removal of oil and dirt from the skin surface and generally contribute to the foaming/lathering of cleansers.

e.g. sodium laureth sulfate, cocamidopropyl betaine, sodium C14-16 olefin sulfonate

  • Humectants – Help retain and attract water.

e.g. hyaluronic acid, glycerin, polyglutamic acid

  • Occlusives – Prevent and slow moisture evaporating from the skin’s surface.

e.g. petrolatum, beeswax (cera alba)

  • Emollients - Soften and smooth skin texture.

e.g. certain plant oils, cocoa butter (theobroma cacoa), shea butter (butyrospermum parkii), dimethicone, mineral oil (paraffinum liquidum)

  • Thickeners – Help maintain product viscosity.

e.g. cetyl alcohol, stearyl alcohol, stearic acid, xanthan gum

 

While anything listed after the top ten has less impact on the skin, there are always exceptions and these ingredients will still be functional/offer benefit to the skin. 

Many active ingredients are often just as effective at lower percentages and much gentler on your skin barrier – less is more (you just need to be patient). Learn more about ingredient percentages here.

Don’t worry if you see antioxidants way down the list, but do worry if you see only one – our skin needs a whole army of water and fat-soluble antioxidants in the fight against pollution. More is more! Common antioxidants used in skincare include: vitamin E, vitamin C and ferulic acid.

  

Ingredients under 1% can be listed in any order

The common ingredients you will usually see at the end of an INCI are as follows:

  • Preservatives - As mentioned earlier, preservatives have a set limit of 1% or less so you will always see these towards the end of an INCI list.

  • Fragrance/Parfum – This indicates that the product contains a blend of fragrance ingredients, as essential oils and synthetic fragrances under 1% don’t have to be listed individually. It is worth keeping in mind, however, that some formulas contain a larger amount of fragrance so you may see this higher up on an INCI.

  • Fragrance allergens - Currently, there are 26 declarable allergens that must be included on the INCI list. This includes a range of natural essential oils and synthetic fragrances, and depends on the percentage used and how long your skin will be exposed e.g. leave-on products (present > 0.001%) or rinse-off products (present >0.01%). 

    e.g. cinnamyl alcohol, limonene, linalool, geraniol, eugenol, hydroxycitronellal

  • Plant extracts – Legally, these must be written in Latin. However, some brands will also add the English translation in brackets. g. rosemary extract = rosmarinus officinalis (rosemary) leaf extract.

  • Dyes/colour additives - always last, after non-colour additives, regardless of concentration. These will be listed by their CI number or common name, depending on where the product is sold. E.g: CI 77891 (Titanium Dioxide), CI 77491, CI 77492, CI 77499 (Iron Oxides), CI 15850 (Red 6 or Red 7), CI 77007 (Ultramarines)