Yet your locks stubbornly remain more lacklustre than luscious. Have you ever considered your shampoo might be to blame?
Research suggests it could be — specifically brands that contain sulphates. These have been used for decades as foaming and cleansing agents. You’ll find them in toothpaste and shower gel as well as most shampoos.
Hair-raising: Shampoos containing sulphates are more likely to make hair turn limp and dry
Recently, though, the cosmetics industry has got itself in a lather over them — partly because of a trend for more ‘natural’ cosmetics containing gentler ingredients, but also because they have been found to fade the colour of highlighted or dyed hair, and affect the results of long-lasting Brazilian hair-straightening treatments.
They are also more likely to make hair that is often styled with heated appliances such as straighteners and tongs turn limp and dry.
As a result, in the past 18 months an increasing number of hair products boasting they are ‘sulphate-free’ have started appearing on supermarket and chemists’ shelves.
So what are sulphates, and do we really need to be cautious of them? In the words of one well-known cosmetics advert: here comes the science bit.
A sulphate is a salt of sulphuric acid (gypsum, or plaster of Paris, is probably the best-known example). With shampoo, two particular sulphates are commonly used: sodium lauryl sulphate (SLS) and sodium laureth sulphate (SLES)
It is these that are being excluded from the new breed of shampoos. Not that there is anything actually dangerous about them — the much-repeated internet rumour that they are potentially carcinogenic is a myth.
Technically called surfactants (a shortened form of ‘surface-active-agents’), sulphates act as cleaning agents to dissolve dirt, boost foam and enable dissolved dirt and oil to remain liquid so they can be rinsed away.
These attributes undoubtedly make sulphates useful ingredients for shampoos: the problem is that not only do some people find they irritate their skin, they can also over-strip hair — like paint stripper.
If your hair is lack-lustre and out of control despite your best efforts, consider switching to a gentler shampoo
‘SLS and related compounds lather well and produce a rich foam, which cleans the hair effectively, but they can irritate the eyes and leave the hair dry,’ says dermatologist Dr Sam Bunting.
‘This is a particular problem for those who colour or straighten their hair regularly, or have very long hair, where the ends can easily get into bad condition.’
Their over-effective cleansing action can also gradually strip hair colour. Fans of Brazilian-style hair-straightening treatments, especially the ones that use a small percentage of formaldehyde to achieve their long-lasting results, will have been advised by salons to avoid sulphate-based shampoos.
Finding an effective SLS-free shampoo used to be difficult, but recent advances in technology mean that there are plenty of shampoos to choose from containing gentler cleansing agents derived from corn, coconut and oats.
‘Gentler surfactants can clean the hair just as effectively as harsher ones,’ says Dr Bunting.
‘The fact that a shampoo produces foam is not a good indicator of how well it works. Gentler surfactants are an excellent choice for most people, especially anyone with processed hair or a sensitive scalp.’
Examples of effective surfactants include cocamidopropyl betaine and sodium lauraminopropionate. ‘These will clean the hair and leave it soft and manageable,’ he says.
Conditioners don’t contain SLS or SLES. On a shampoo’s ingredients list the chemicals will usually appear second. But if you scan the list closely it can be confusing, since many of the ingredients, even in designated ‘sulphate-free’ shampoos, may still end in ‘-sulphate’.
‘The one we use as a foaming agent — sodium coco sulphate — is derived from coconut,’ says a spokesman for Green People, a company that specialises in organic body-care products and eschews damaging surfactants.
So, if you fancy trying a more gentle shampoo, the key is to look for the words ‘sulphate-free’ on the packaging. This will mean that the product is free from sodium lauryl sulphate and sodium laureth sulphate, no matter what other sulphates appear as an ingredient.
