What Is Sodium Myristyl Sulfate?
Sodium Myristyl Sulfate, also known as sodium tetradecyl sulphate, is a surfactant made by attaching a sulfate group to myristyl alcohol, a fatty alcohol most often sourced from coconut or palm kernel oil. The result is a white to off-white powder or flakes that dissolve readily in water and generate a rich foam.
The ingredient was introduced to personal care labs in the mid-twentieth century, when chemists were searching for plant-based alternatives to traditional soap. Its consistent performance in both hard and soft water quickly made it popular with shampoo and body wash formulators. Today it is produced on an industrial scale through a two-step process: first myristyl alcohol is reacted with chlorosulfonic acid or sulfur trioxide to create the sulfate ester, then the mixture is neutralized with sodium hydroxide to yield the final salt.
You are most likely to spot Sodium Myristyl Sulfate in foaming cleansers, shampoos, shower gels, facial washes, bubble baths, liquid hand soaps, some makeup removers and even toothpaste. It also shows up in lotions, hair conditioners and sunscreens where it helps blend oil and water into a smooth, stable mixture.
Sodium Myristyl Sulfate’s Cosmetic Benefits/Uses
Below are the main roles this ingredient plays in beauty formulas
- Cleansing: Lowers the surface tension of water so oils, dirt and product buildup can be lifted away and rinsed off easily, giving skin and hair a fresh feel
- Emulsifying: Keeps water-based and oil-based ingredients mixed together which prevents separation and gives creams, lotions and conditioners a uniform, pleasant texture
Who Can Use Sodium Myristyl Sulfate
Products containing Sodium Myristyl Sulfate generally suit normal and oily skin because the ingredient excels at removing excess sebum and buildup. People with dry or easily irritated skin may find it too cleansing which can leave the skin feeling tight or stripped; the same caution applies to those with a compromised skin barrier or chronic conditions like eczema. Hair types prone to dryness or color treatment can also experience extra dryness if this surfactant sits high on the ingredient list.
The compound is typically derived from plant sources such as coconut or palm kernel oil, so it is suitable for vegans and vegetarians provided the rest of the formula follows the same ethical sourcing.
No evidence indicates that Sodium Myristyl Sulfate poses specific risks to pregnant or breastfeeding women when used in rinse-off or leave-on cosmetics, yet this is not medical advice. Anyone expecting or nursing should review all personal care products with a qualified healthcare professional to stay on the safe side.
Sodium Myristyl Sulfate does not increase skin photosensitivity, so routine sun exposure precautions rather than special measures are sufficient. The ingredient also rinses away easily and does not interfere with most other topical actives which makes it flexible in layered routines.
Potential Side Effects/Adverse Reactions
Side effects from topical use of Sodium Myristyl Sulfate vary between individuals. The following list outlines potential reactions that could occur although most people will not experience them when the ingredient is formulated and used correctly.
- Skin dryness or tightness due to lipid removal
- Redness or stinging on sensitive or compromised skin
- Itching or mild burning sensations during use
- Allergic contact dermatitis in rare cases
- Eye irritation if the product accidentally enters the eyes
- Excess scalp dryness or increased frizz in hair care applications
If any of the above reactions occur discontinue use immediately and seek advice from a healthcare professional or dermatologist.
Comedogenic Rating
Rating: 1 out of 5
The sulfate group makes Sodium Myristyl Sulfate highly water soluble, so it rinses off instead of lingering in pores. While the 14-carbon myristyl chain has a slight potential to lodge in follicles, real-world use shows little evidence of clogged pores, especially because the ingredient is almost always found in wash-off products. Therefore it sits at the low end of the scale.
Acne-prone skin generally tolerates this ingredient well, particularly in cleansers and shampoos that are not left on the skin for long.
Note that finished formulas can vary: heavy cream bases or additional oils may shift a product’s overall comedogenicity even if this single surfactant is low risk.
Summary
Sodium Myristyl Sulfate is valued for two key jobs: cleansing by lifting away oil and debris through micelle formation, and emulsifying by holding water and oil together for stable, smooth textures. Its foaming ability and reliability in different water conditions keep it on the shelves even though bigger names like SLS often get the spotlight.
Most safety assessments classify it as low toxicity and non-sensitizing when properly formulated, though it can be drying or irritating for some users. As with any new skincare or haircare product, doing a small patch test first is a sensible step to rule out personal sensitivities.