What is Stearic Acid and what does it do in products?

What is Stearic Acid and what does it do in products?

EPA Safe Ingredient - YES
EWG® Score – 1
EU and Canada Approved – YES
Plant-based – Yes – palm oil
Skin Irritant - Mild
Environment Hazard – Relatively Low
Biodegradable – Readily
CAS – 57-11-4

What is Stearic Acid

Stearic Acid is one of the most common saturated fatty acids found in nature— primarily through animal and vegetable fats.  It is used in cosmetic and skincare products around the world.   

Why do we use Stearic Acid

We use stearic acid in our hair and skincare line of products because it is a surfactant and emulsifying agent.  It helps other emollients bind together and stabilizes the formula that contain fragrances.  Stearic Acid can moisturize the skin and it can protect the hair shaft. By using stearic acid, the hair will be protected and not feel heavy or look dull. 

Is Stearic Acid safe to use? Is it nontoxic?

The triple pressed stearic acid that we use is safe and not toxic to the environment. However, using pure stearic acid can cause skin, eye and respiratory irritation. According to a NOAA report there is no current information available if it is toxic to aquatic life.  Some research has been done and documented about the oral toxicity of stearic acid.  Since we do not deal in food items, we will not add unnecessary information to this article.

In Summary

Rustic Strength uses stearic acid in our lotions and conditioners to help with moisture retention and protection of the hair shaft.  It is widely accepted material in cosmetics and food.  Stearic acid is readily biodegradable with little to no toxicities. 

If you have any questions regarding this or any other ingredients we use feel free to reach out to our email: customercare@rusticstrength.com  We would be more than happy to answer your questions. 


We invite you to do your own research! 

Scientific journals and articles are the foundation of evidence-based decisions at Rustic Strength. Blogs can provide helpful information. However, if it can not cite scientific articles, its claims stand on little. 


EPA Safe Ingredient - https://www.epa.gov/saferchoice/safer-ingredients#scil

EWG® Score = https://www.ewg.org/skindeep/ingredients/706311-STEARIC_ACID/

EU - https://echa.europa.eu/substance-information/-/substanceinfo/100.000.285

Canada - https://www.canada.ca/en/health-canada/services/consumer-product-safety/cosmetics/cosmetic-ingredient-hotlist-prohibited-restricted-ingredients/hotlist.html

Plant-based -  SDS and manufacturers statement on file

Skin Irritant - https://journals.sagepub.com/doi/10.3109/10915818709098563

Environment Safe - https://pubchem.ncbi.nlm.nih.gov/compound/Stearic-Acid#section=Toxicity

Biodegradable - https://echa.europa.eu/registration-dossier/-/registered-dossier/14937/5/3/2#

Common - https://en.wikipedia.org/wiki/Stearic_acid

Emulsifying - https://www.mdedge.com/dermatology/article/78248/aesthetic-dermatology/stearic-acid?reg=1&icd=login_success_email_match_norm

Safe - https://journals.sagepub.com/doi/10.3109/10915818709098563

not toxic - https://online.personalcarecouncil.org/ctfa-static/online/lists/cir-pdfs/FR777.pdf

pure stearic - https://www.medicalnewstoday.com/articles/stearic-acid#what-is-it

NOAA - https://cameochemicals.noaa.gov/chris/SRA.pdf

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