As people start trying to use healthier and safer body and home care products, they start to actively avoid certain key ingredients. One of the most common sets of ingredients to avoid is known amongst the healthy living crowd and blogosphere as “sulphates” (or the American spelling, “sulfates”, not to be confused with sulphites/sulfites). There is a reason for this. Two very popular and well-known sulphates are sodium lauryl sulphate (SLS) and sodium laureth sulphate (SLES). Both of these chemicals are common detergents and have been shown to cause skin irritation in sensitive individuals. There are a number of other detergent sulphates that tend to be lumped into this grouping, but what *are* sulphates? Are they really a bad thing?
A “sulphate” is any chemical compound that has a specific anionic (negatively charged) group of chemical elements attached, containing one sulphur atom and four oxygen atoms. In a chemical formula, this is written as SO4. The name of this chemical compound is generally found at the end of a chemical name, such as in sodium lauryl sulfate, but the presence of the sulfate ion in a chemical does not imbue that chemical with specific properties. Instead, it is the combination of this ion with certain other chemicals that creates a detergent and causes irritating properties. Not all sulphates are created equal. In fact, some may help to heal and soothe your itchy skin.
So how do you know which sulphates to avoid?
The sulphates being targeted by this broad suggestion to avoid sulphates are detergents and surfactants. Surfactants are molecules that reduce the surface tension of water and allow it to wet items more thoroughly. One particular kind of surfactant is a detergent, which is a man-made chemical compound which helps to dissolve dirt and oil by attracting both water molecules and oils and dirt particles, and connecting them together. Detergents tend to be both more harsh and more effective than other surfactants, and more effective under varied water and soil conditions. On the skin, detergents tend to strip away more natural oils than other surfactants, causing the skin to become dry, and often damaging the skin’s barrier layer. These are the sulphates that people who are avoiding sulphates are trying to avoid.
Sulphate-based detergents people are actually trying to avoid:
(Some of them aren’t really sulphates, but they are similar in irritating ability and operation to the sulphates on the list. Milder means slightly less harsh. It does not mean non-irritating. Not a complete list.)
- Sodium lauryl sulphate (SLS)
- Sodium laureth sulphate (SLES)
- Ammonium lauryl sulphate
- Ammonium laureth sulphate
- Sodium dodecyl sulphate
- Sodium coco sulphate
- Sodium lauryl sulfoacetate (milder)
- Sodium lauroyl isoethionate
- Methyl cocoyl taurate (milder)
- Methyl lauryl taurate (milder)
- Sodium lauroyl taurate (milder)
- Disodium laureth sulfosuccinate
- Sodium cocoyl isoethionate (milder)
- Sodium lauroyl sarcosinate
- Sodium lauroyl methyl isoethionate
- Sodium lauryl ether sulphate
- Lithium dodecyl sulphate
- Sodium dodecylbenzenesulfonate
- Sodium myreth sulphate
- Sodium alkylbenzene sulphonate
- Ammonium xylenesulphonate
- Sodium xylenesulphonate
- TEA Lauryl sulphonate
- Sodium C14-16 olefin sulphonate
- Sodium socoyl sarcosinate (milder)
- Ethyl PEG-15 cocamine sulphate (milder)
- Dioctyl sodium sulphosuccinate (milder)
- Sodium lauryl glucose carboxylate (milder)
- Sodium cocoyl glycinate (milder)
People generally view cocamidopropyl betaine and other betaines as less irritating and safer, but they can be just as irritating as the above detergents.
(Many of these forms have risks if used inappropriately, or even when used appropriately, but these risks have nothing too do with the reasons why people avoid “sulphates”. Not a complete list.)
- Iron (II) sulfate – form of iron in mineral supplements
- Iron (III) sulfate – medical styptic and astringent, used in dyeing to help dyes “stick” to fibres
- Magnesium sulphate – Epsom salts, useful for soothing skin irritation
- Potassium aluminum sulphate – an acidic molecule not suitable for direct skin contact but which is used in chemical reactions in natural dyeing to help affix the dye to the fabric’s fibres
- Lithium sulphate – used to treat bipolar disorder, as well as being used in batteries, solar panels, and cement
- Sodium sulphate – known as Glauber’s salt, used previously as a laxative, now used for making detergents, soda ash, and paper
- Sodium bisulphate – used for cleaning products, lowering the pH of swimming pools, and in chicken litter (to reduce urine odour)
- Potassium sulphate – fertilizer
- Calcium sulphate – tofu coagulant, used to make gypsum and plaster of Paris, moisture indicator, and dessicant
- Potassium bisulphate – used to make potassium bitartrate for wine making
- Barium sulphate – contrast agent for x-rays and other medical testing procedures, paint pigment, paper brightening agent, drilling fluid ingredient, plastic filler, root canal lining, and more.
- Scandium sulphate – seed treatment to improve germination rates
- Copper sulphate – corrects copper deficiencies in soil, colouring agent, used in printer ink and hair dye
- Zinc sulphate – used to treat zinc deficiency, medical astringent, used in production of rayon, used in animal feeds, toothpastes, and in the beer brewing process
- Aluminum sulphate – used in purification of drinking water, waste water treatment, and paper manufacturing
As you can see, the statement, “Avoid sulphates” is not really the whole or true picture when trying to avoid harsh detergents. Many sulphates have useful places in out lives and shouldn’t be avoided out of hand. We can, however, do the research and identify specific sulphate-based detergents to avoid if we want to maintain healthier skin.
Have I missed any? Comment below.