Sulfates, commonly found in cosmetics, have sparked considerable debate. This is an update of the post I wrote 11 years ago and the debate still fires on. Their effectiveness as surfactants and foaming agents, particularly Sodium Lauryl Sulfate (SLS), Sodium Laureth Sulfate (SLES), and Ammonium Lauryl Sulfate (ALS), makes them a popular choice in soaps and shampoos.

The controversy arises from their potential to strip natural oils, possibly leading to skin irritation. However, this concern may be overhyped as many formulations utilise sulfates in ways that reduce their harshness. The disagreement stems more from varied consumer experiences and preferences rather than a clear scientific consensus on their negative effects. It also stems from brands then reflecting this concern back as marketing-hype creating a feedback loop that suddenly becomes ‘fact’.

Initial Thoughts and Research Approach

A Google search for “Sulfates in Cosmetics” yields titles like “Dangers Of Sulfates in Skin Care and Personal Care Products” and “Sulfates: Are These Harmful Ingredients in Cosmetics?”, highlighting the negative perception surrounding these ingredients. But why is this the case?

Understanding Sulfates

So, what exactly are sulfates? Known as surfactants or detergents, they foam up to cleanse away dirt, grime, grease, and other residues from the skin. While they are effective cleansers, they are also known to cause dryness, potentially leading to skin irritation. However, when formulated with enough humectants and emollients, these drying effects can be mitigated.

The most common sulfates are the following, found in many shampoos, facial washes, and body cleansers:

• Sodium Lauryl Sulfate (SLS): Known for its foaming properties, SLS is commonly found in shampoos, toothpaste, and cleansers.
• Ammonium Lauryl Sulfate (ALS): Similar to SLS, ALS is used for its foaming effect in various cleaning and personal care products.
• TEA-Lauryl Sulfate: Often used in shampoos and body washes, this sulfate is known for its effectiveness in removing oils and dirt.
• Sodium Myreth Sulfate: Similar to SLES, it’s used in personal care products for its cleansing and emulsifying properties.
• Sodium Trideceth Sulfate: Typically found in skincare and haircare products, it acts as a surfactant and emulsifier.

How do Sulfates function?

Sulfates function primarily as surfactants in cosmetics and cleaning products. Here’s a simplified explanation of how they work:

• Attracting Oil and Water: Sulfates have a unique molecular structure that enables them to attract both oil and water.
• Breaking Down Dirt and Oil: In shampoos or soaps, sulfate molecules help break down dirt and oil on your skin or hair.
• Forming Lather and Rinsing Clean: The sulfate molecules form micelles around oil and dirt particles, creating a lather that is then washed away, leaving a clean surface.

Their ability to interact with both water and oil makes sulfates highly effective cleaning agents for everything from your face to your Y-fronts.

Why people are scared of sulfates? Truth and Misinformation

The fear and controversy surrounding sulfates in cosmetics stem from concerns about their potential to cause skin irritation, dryness, and hair color stripping; this is true but only when badly formulated. It’s like saying drinking a cup of water is dangerous because you can drown in a river. Much of the fear seems to be fueled by misinformation and lack of understanding rather than solid scientific evidence.

Sulfates like sodium lauryl sulfate (SLS) and sodium laureth sulfate (SLES) are synthetic foaming agents commonly found in shampoos, body washes, and facial cleansers. They have been blamed for various issues, but according to Health Canada, there is no evidence showing that SLS poses a significant safety risk when used as directed in cosmetics​​ (source).

The misinformation surrounding sulfates and other cosmetic ingredients is largely amplified by social media, which has become a source of ‘whisper campaigns’ that often spread fear and confusion among consumers (good source to read). This leads to an ‘architecture of misinformation’ that can discredit the beauty industry and overshadow scientific evidence and expert opinions​​.

In the case of ‘clean beauty’ and ‘chemical-free’ products, the terms are often used without clear definitions, contributing to the confusion. There is no such thing as ‘chemical-free’ anything; we and everything around us are made of chemicals. It’s important to understand that the mere presence of chemicals in a product doesn’t inherently make it harmful​​! It’s a marketing gimmick, so don’t be fooled by it.

Regarding sulfates specifically, the concerns are often overhyped. While it’s true that sulfates can strip natural oils, leading to dryness or irritation for some people, this does not mean they are harmful to everyone or should be universally avoided. It’s crucial for consumers to understand their own skin and hair type and choose products accordingly.

Sulfates vs Sulphates

the difference between ‘sulphates’ and ‘sulfates,’ the distinction is primarily regional spelling. ‘Sulfates’ is the preferred spelling in American English, while ‘sulphates’ is used in British English. Chemically, they refer to the same group of compounds, which are salts or esters of sulfuric acid containing the anion SO4^2− or the divalent group -OSO2-O-. The different spellings do not indicate any difference in chemical structure or properties.

The Debate on Sensitivity

So, is it true that it causes sensitivity? In October 2007, NICNAS – Australia’s National Industrial Chemicals Notification and Assessment Scheme (source) reported that Sodium Laureth Sulfate (one of the most commonly used sulfates in cosmetics) “is a skin and eye irritant in rabbits, and skin irritation has been observed in clinical studies in humans. Indeed, in the human 4-hour patch test for irritation, SLS is used at 20% as a positive control to identify substances or preparations that would be on the borderline for classification as irritant. SLS is also reported to irritate the respiratory tract.” Through tests on Beagle dogs, SLS was not found to be carcinogenic or genotoxic, so good news there, although not so much for the dogs.

Insights from the International Journal of Toxicology

To my next port of call, the International Journal of Toxicology (source), specifically to the Final Report of the Amended Safety Assessment of Sodium Laureth Sulfate and Related Salts of Sulfated Ethoxylated Alcohols. Before getting stuck into the journal, the abstract outlines that “Sodium and ammonium laureth sulfate have not evoked adverse responses in any toxicological testing” and that “Sodium laureth sulfate was demonstrated to be a dermal and ocular irritant but not a sensitiser”.

Meaning that SLS irritates the skin, but through prolonged use, it doesn’t appear to increase the sensitivity of the skin. However, “in practice they are not regularly seen to be irritating because of the formulations in which they are used”. So by themselves they do cause irritation, it’s safe to conclude that by now, but when formulated effectively, the irritation can disappear. It’s about quantity and use, a very fine art in cosmetology and my initial belief seems to be holding some weight.

Conclusion and Personal Perspective

Regarding sulfates specifically, the concerns are often overhyped. While it’s true that sulfates can strip natural oils, leading to dryness or irritation for some people, this does not mean they are harmful to everyone or should be universally avoided. It’s crucial for consumers to understand their own skin and hair type and choose products accordingly.