Alanine

What it is

Alanine is an amino acid, one of the basic building blocks that proteins are made from — including the keratin of hair. It occurs in the body and in food and is usually produced biotechnologically by fermentation for cosmetic purposes. The stated origin “biotechnological” captures that correctly and is factual information, not an assessment.

In hair care products alanine is used as a moisture-binding constituent. Amino acids are small, water-soluble molecules that bind water and can penetrate the hair fibre. Unlike most cosmetic constituents, the substance itself is very well characterised — it has long been known from nutrition, medicine and biochemistry.

Why

• Why “very low risk”: this is an amino acid native to the body and present in food, used in cosmetics at low proportions. Irritation or sensitisation potential is not to be expected in this use. This classification rests on the very good general knowledge of the substance, not on product-specific test data.
• The distinction still matters here: “native to the body” is not a safety argument in itself. There are endogenous substances that are problematic at high doses. What is decisive is quantity and use — and both are unremarkable here.
• On the effect claim: that amino acids bind water is well established. The addition “supports cuticle repair” in the short field goes beyond that. Cosmetics can smooth, fill and soften damaged hair; genuine repair in the biological sense does not take place in dead hair. That is a language problem, not a safety problem.
• Without a use level the same applies here: the classification concerns the substance in customary cosmetic use, not a specific product.

When the assessment differs

• Sensitive or pre-damaged scalp: here too what matters is the tolerance of the whole product. This constituent is not the typical trigger.
• Expectations: “very low risk” is a statement about tolerance and not a confirmation of a visible care result.
• The cosmetic context must be considered separately from the food or supplement context. Statements on this page apply only to external use.

Open questions

• Regulatory status: not examined; the entry in the EU CosIng database must be checked, with its date.
• Evidence for the care effect in the finished product: not examined here.
• Concentration in a specific product: not available.
• Environmental data: not examined. For an amino acid native to the body the question is different from that for synthetic polymers; it was nevertheless not examined here.

Related substances

Applies to: Amino acids and peptides

• Acetyl Tetrapeptide-3 — Peptide (hair density, efficacy evidence limited)
• Arginine — Amino acid (conditioning, pH adjustment)

Further substances from the same group for which a long-form assessment already exists.