Diethanolamine

dye-ETH-an-ol-AM-een

pH Adjuster, Surfactant 3/10 Safety Not CGAvoid Synthetic Vegan

What Is Diethanolamine?

An organic chemical used as a pH adjuster and foam booster in hair products. It can react with other ingredients to form potentially carcinogenic nitrosamines.

Source: Synthetic organic compound

Origin: Synthetic

Also known as: DEA, 2,2-Iminodi(ethanol)

What Does Diethanolamine Do to Your Hair?

Acts as a pH adjuster to maintain optimal product acidity. Also functions as a foam booster and emulsifier. However, DEA can react with nitrosating agents in formulations to form N-nitrosodiethanolamine (NDELA), a suspected carcinogen.

Best For

None recommended

Not Recommended For

All hair types, especially with long-term use

Concentration Matters

0.5-2% where still used

Hair Type Compatibility

1A Straight Fine
1B Straight Medium
1C Straight Coarse
2A Wavy Fine
2B Wavy Medium
2C Wavy Coarse
3A Curly Loose
3B Curly Tight
3C Curly Corkscrew
4A Coily S-Shaped
4B Coily Z-Shaped
4C Coily Tight

Method Compatibility

Curly Girl (CG) Method: Avoid
CG Avoid

Safety & Regulation

3/10
AvoidCautionSafe

Significant concern about nitrosamine formation. The EU restricts DEA in cosmetics and requires products be free of nitrosating agents. California Proposition 65 lists it as a possible carcinogen. FDA advises against use with nitrosating agents.

FDA Status: Restricted

FDA advises manufacturers to avoid combining DEA with nitrosating agents. EU restricts maximum concentration to 0.5% in cosmetics.

EWG Score: 6/10

HairAide Verdict

Best avoided due to nitrosamine formation risk. Many safer alternatives exist for every function DEA performs. Check your product labels and choose reformulated products that have eliminated DEA.

Products That Contain Diethanolamine

Some older-formula shampoos and conditioners (being phased out)

Alternatives to Diethanolamine

If you want to avoid Diethanolamine, look for products with these ingredients instead:

Cocamidopropyl Betaine, Cocamide MIPA, plant-derived alternatives

Frequently Asked Questions

Is Diethanolamine safe for hair?

Diethanolamine has a safety rating of 3/10 and may be problematic for many hair types. Significant concern about nitrosamine formation. The EU restricts DEA in cosmetics and requires products be free of nitrosating agents. California Proposition 65 lists it as a possible carcinogen. FDA advises against use with nitrosating agents.

Is Diethanolamine bad for curly hair?

Diethanolamine is not CG-method approved. Curly hair types may want to avoid this ingredient or use products containing it sparingly.

Is Diethanolamine CG-method approved?

No, Diethanolamine is not approved for the Curly Girl method.

What can I use instead of Diethanolamine?

Some alternatives to Diethanolamine include: Cocamidopropyl Betaine, Cocamide MIPA, plant-derived alternatives

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