The front of a cosmetic package is marketing and it is loosely constrained. The back is a regulated document. Learning to read the back takes about ten minutes and it will change what you buy more than any review ever will, because it lets you check the claim against the formulation yourself.
What INCI is and why it looks like that
INCI stands for International Nomenclature of Cosmetic Ingredients. It is a standardised naming system so that the same substance carries the same name on a package anywhere it is used. It is why aloe vera appears as Aloe Barbadensis Leaf Juice, water appears as Aqua and vitamin B3 appears as Niacinamide.
Plant derived ingredients use botanical Latin. Synthetics use chemical names. Neither form tells you anything about safety or quality, and the assumption that Latin means gentle and chemical means harsh is the single most expensive misconception in this category.
The ordering rule, and the one per cent line
Ingredients are listed in descending order of concentration down to one per cent. Below one per cent, they may be listed in any order the manufacturer chooses.
This is the most useful thing on the entire package, because it means you can locate approximately where the one per cent line falls and read everything after it as trace. Two reliable markers:
- Preservatives. Phenoxyethanol is used up to a regulated maximum of one per cent, so it usually sits at or just above the line. Other common ones include benzyl alcohol, sodium benzoate, potassium sorbate and the ethylhexylglycerin often paired with phenoxyethanol.
- Thickeners, chelators and pH adjusters. Xanthan gum, carbomer, disodium EDTA, sodium hydroxide and citric acid are almost always used well below one per cent.
Once you spot one of those, everything downstream is present in small quantities. If a product is sold on its ceramide content and ceramides appear three places after phenoxyethanol, alongside four botanical extracts, you are looking at a marketing ingredient rather than a functional one.
Find the preservative. Everything after it is a rounding error.
Useful concentrations, roughly
| Ingredient | Typically effective range | Where it should appear |
|---|---|---|
| Glycerin | 3 to 10 per cent | Top third of the list |
| Niacinamide | 2 to 5 per cent | Upper half, above the preservative |
| L-ascorbic acid | 10 to 20 per cent | Near the top, usually second or third |
| Salicylic acid | 0.5 to 2 per cent | Around or below the line, so check the front claim |
| Azelaic acid | 10 per cent and above | Near the top |
| Zinc oxide as a sunscreen filter | Often 10 to 25 per cent | Near the top, or in a separate filter declaration |
| Retinol | 0.1 to 1 per cent | Below the line, so the stated percentage matters more than position |
| Ceramides | Low percentages, but as a functional blend | Should sit with cholesterol and fatty acids, not alone at the end |
Note the two exceptions. Some genuinely useful ingredients are active at fractions of one per cent, so position alone cannot condemn them. That is why retinol products state a percentage and why a good ceramide formulation names several lipids together rather than one, as discussed in the retinoid explainer.
Where fragrance hides
Fragrance appears as Parfum or Fragrance, and it is a single entry that can represent dozens of individual components. That is permitted for commercial confidentiality.
Specific fragrance allergens must be declared separately above defined thresholds. The names you will see include linalool, limonene, citronellol, geraniol, eugenol, coumarin and benzyl salicylate. If a label lists parfum followed by a string of those, it is a substantially fragranced product regardless of what the front says.
Two more traps. Unscented is not a regulated equivalent of fragrance free, and can mean a masking fragrance has been added to cover a raw material smell. And essential oils, listed under their botanical names, are fragrance. Lavender oil, citrus peel oils and tea tree oil are among the more frequent causes of contact reactions, and being plant derived confers no advantage here.
This matters most on freshly shaved skin, where permeability is temporarily increased, as set out in shaving irritation, the real causes.
What the front of the pack does not have to mean
| Claim | What it actually tells you |
|---|---|
| Dermatologically tested | Some testing involving a dermatologist occurred. Not a result, not an endorsement |
| Hypoallergenic | Not a regulated term with a defined threshold. Read the list instead |
| Non-comedogenic | Based on varied testing methods, some not on human facial skin |
| Natural | Not a defined term in cosmetic regulation |
| Chemical free | Impossible. Water is a chemical |
| Clinically proven | Check what was measured, on how many people, and by whom |
| With ceramides, with retinol | Present. No statement about quantity |
| For men | A fragrance and packaging decision, not a formulation one |
The ten second assessment
- Read the first five ingredients. That is most of the product. Water, then the main emollients, humectants and any high load actives.
- Find the preservative. Mentally draw a line there.
- Check whether the hero ingredient is above the line. If it is below and no percentage is stated, discount the claim.
- Scan for parfum and the named allergens. Decide whether you want them on that part of your body.
- Check the format. An oxidation prone active such as L-ascorbic acid or a retinoid in a clear jar with a wide opening will degrade. Opaque, airless packaging is a genuine formulation decision, not a design flourish.
Who regulates this in the UK
Cosmetic products placed on the UK market must comply with the UK cosmetics regulation, which sets out the permitted, restricted and prohibited substance lists, the labelling requirements including INCI ordering and allergen declaration, and the requirement for a safety assessment before a product is sold.
Products making medicinal claims, or containing ingredients that act pharmacologically, fall under medicines regulation instead and are overseen by the Medicines and Healthcare products Regulatory Agency. That distinction is why some strengths of an active are available on a shelf and others only on prescription.
Once you can read a label, the routine question becomes much simpler, because you can verify whether a product does what the three step approach in the minimum effective routine requires of it, rather than trusting the front of the box.