Colouring Agent/Pigment

Lactoflavin

INCI: LACTOFLAVIN

Reviewed by Daisy · Last updated 14 Aug 2026

A B vitamin form used primarily as a colourant in hair and cosmetic products

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What Is Lactoflavin?

Lactoflavin is a form of riboflavin (vitamin B2) that appears in cosmetic formulations, primarily as a cosmetic colourant and hair-dyeing agent. It is derived from or chemically related to riboflavin, a water-soluble B vitamin essential for various metabolic processes in the body.

In skincare and haircare products, lactoflavin functions mainly as a pigment rather than as a nutritional or therapeutic agent. Its role is to impart colour to formulations and, in hair products, to contribute to dyeing or tinting effects.

How It Works

Lactoflavin functions as a cosmetic colorant by absorbing and reflecting light at specific wavelengths, producing visible colour in products. In hair applications, it deposits colour onto the hair shaft through standard dyeing mechanisms.

Whilst riboflavin itself has metabolic roles in the body, topical application of lactoflavin in cosmetic products does not necessarily deliver the same systemic benefits. The ingredient works primarily at the surface level as a pigment.

Clinical Evidence & References

Evidence specifically examining lactoflavin's efficacy or safety in topical skincare formulations is limited. Most research on riboflavin relates to systemic deficiency and oral intake rather than cosmetic application.

Riboflavin deficiency can affect skin, hair, and nail health when intake is inadequate, but this does not mean that topical lactoflavin will reverse or prevent such deficiencies. Further research would be needed to establish any measurable benefit of lactoflavin as a cosmetic ingredient beyond its colouring function.

How to Use

Lactoflavin is typically incorporated into formulations at concentrations determined by the desired colour intensity and regulatory guidelines. Products containing lactoflavin as a colourant should be used according to product instructions. Patch testing before use on hair is advisable if you have sensitive scalp or are prone to contact reactions.

Safety & Precautions

Lactoflavin is generally recognised as safe in cosmetic formulations within approved concentrations. As with all cosmetic colorants, individuals with known sensitivity to dyes or B vitamins should patch test first.

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Other forms of Lactoflavin

These appear on ingredients lists under different names but are the same substance. Lactoflavin is the common form.

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