Derived from a biotechnological or synthetic process, the dihydroxyacetone (DHA) is a coloring agent found in certain hair care and self-tanning products. Let's focus on the use of this compound on hair.
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Dihydroxyacetone, an effective ingredient for hair?
Summary
- Dihydroxyacetone in a nutshell
- Dihydroxyacetone for hair: the active ingredient in natural hair dyes
- The precautions for using DHA-based tanning products
- Source
Published February 22, 2022,
updated on August 7, 2024,
by
Maylis, Chemical Engineer
—
4 min read
Dihydroxyacetone in a nutshell.
The dihydroxyacetone is a triose molecule, meaning it is a sugar composed of three carbon atoms. It is naturally found in plants such as chestnut bark. However, it can also be obtained through a biotechnological process. This involves a step of microbial fermentation from glycerin extracted from certain plants like sugarcane, beetroot, corn, rapeseed, among others. The DHA thus obtained appears as a white crystalline powder that is soluble in water and ethanol but insoluble in oil.
DHA acts as a coloring agent ; it is primarily used as an active ingredient in self-tanning products and natural hair dyes. Upon contact with the amine functions carried by the amino acids present in the dead skin cells and/or hair fibers, DHA reacts according to the Maillard reaction to form heterogeneous polymers called melanoidins responsible for the brown color.
Dihydroxyacetone for hair: the active ingredient in natural hair dyes.
Dihydroxyacetone (DHA) is a coloring agent that is typically used in the composition of natural dyes, also referred to as non-oxidative dyes. Among other things, it helps to conceal the white hair that can appear over time.
As a reminder, traditional hair dyes, known as oxidative, color the hair by replacing its natural pigmentation. This type of dye acts on the hair's structure, as it penetrates the cuticles. This allows the hair's melanin to be replaced with the chosen color. However, it's worth noting that this type of dye can be harsh, hence the importance of using suitable care products (moisturizing and repairing) after its application.
Unlike traditional dyes, natural non-oxidizing dyes rich in DHA color hair without altering their structure. They act only on the surface, in contact with the keratins present on the hair fibers. Using this type of treatment allows the hair to maintain its shine because the keratin remains intact. Let's remember that keratin is a natural protein that acts as a protective barrier for hair fibers by forming the hydrolipidic film.
It's important to note that these act on a superficial level, DHA-based colorations are, however, temporary. To maintain the coloration, it is therefore necessary to space out shampoos and reapply the color a few weeks later. Moreover, prior preparation can help prolong the coloration. A scalp scrub is particularly necessary to remove dead cells and revitalize the hair. You can thus use our scalp scrub PHA 5% + jojoba beads beforehand. This pre-shampoo exfoliating gel gently removes dead cells for a healthy and balanced scalp.
The precautions for using DHA-based tanning products.
The use of DHA in hair dyes has recently been regulated. The maximum concentration of DHA allowed in hair care products is now 6.25%. Regardless, this active ingredient is not subject to any contraindications. It can be used without fear, knowing that it does not cause any adverse effects. However, since hair dyes can contain other ingredients, a patch test on the inside of the elbow with the product in question is still recommended to avoid allergic reactions. In case of redness or itching, the use of the product should be discontinued.
Source:
CIRIMINNA R. & al. Dihydroxyacetone: An updated insight into a significant bioproduct. ChemistryOpen (2018).
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