Can you ever judge a product by its ingredients? Judy Johnson asks the skin care experts how to read the label

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While it may seem a little reductive to try and solve your sensitive skin issues  by avoiding individual ingredients, it is the simplest and most obvious place to start in such a complex problem. As with a food intolerance that you can’t quite get to the bottom of, the easiest way to diagnose the root of the issue is by a process of elimination, and given the number of ingredients in a single skin care product it’s difficult to get much further into the detail without the help of a dermatologist or a science degree. But how much can you ever really know about a product’s suitability for sensitive skin from its ingredients list?

Every beauty product has an ingredients list by law, usually printed in the smallest font possible (thanks, packaging folk). But while I’ve written before about how I try to avoid obvious allergens such as Methylisothiazolinone  (MI), SLS  and fragrance in my skin care, I still experience reactions - because there is so much more to a label than meets the (strained) eye.

I’ve asked some of the industry’s smartest skin care experts to find out why this is, and whether it's possible to read an ingredients list in a way that's helpful for sensitive skin…

First off, what is an INCI list?

"In the EU, cosmetic ingredients are labelled using their INCI name,” says Ian Taylor, Cosmetic Scientist for Green People . "This stands for the International Nomenclature of Cosmetics Ingredients, and in general uses either the chemical name, or for plants the Latin binomial name of the plant together with the part of plant used and whether it is an extract, oil, powder, or whatever.”

Is it written in any kind of order?

Yes - but it’s still not particularly transparent if you want to know how strong the formula is.

"Ingredients are listed in descending order of weight, i.e. with the ingredients present in largest quantities appearing first in the list,” explains Ian. "This rule ceases to apply for most ingredients present at levels of less than 1% of the total.” That means once you hit anything below 1%, the order is meaningless.  "The exceptions are colourants (other than those intended to colour hair) which may be listed at the end of the ingredient list.”

Does an INCI list include everything that’s in the product?

Sadly not (imagine how small the font would have to be then?) - which is why you might never know what you’ve reacted to if you don't get on with a product, as Ian explains. "Some ingredients escape being included in the list because they are either unavoidable impurities in the raw materials used; subsidiary technical materials used in the manufacturing processes but which are not present in the final product; or fragrance ingredients which can be listed by the blanket terms of ‘parfum’ or ‘aroma’.”

This is why I try to avoid all products with ‘parfum’ listed - better to go fragrance-free altogether  than to try and work out which ingredient causes a reaction.

However, if a fragrance ingredient is listed it might be trouble

There are 26 fragrance compounds that have to be specified if used, due to the fact that they’re the most common to cause an allergic reaction or sensitivity when applied topically. They’ll be listed on the product if they’re at levels of greater than 0.01% in rinse-off products or 0.001% in leave-on products, Ian tells me, regardless of whether they’ve been added as an isolated chemical or they’re naturally occurring in an essential oil (despite the latter meaning they’re less likely to cause problems).

So what else won’t an ingredients list tell you?

"An ingredients list won’t tell you how an ingredient was produced, or even necessarily what its origin is,” Lorraine Dallmeier, Director of Formula Botanica  tells me. "A perfect example is a carrier oil - it might be unrefined which means that it hasn’t had any of its unsaponifiables (all the goodies in the oil) stripped out of it, but it might have been refined, deodorised and undergone chemical treatment to make sure it doesn’t have a strong scent or colour. The ingredients list won’t tell you any of this because both refined and unrefined oils have exactly the same INCI name.”

Even the formulators can have issues when it comes to ingredients. "When reading the label, you also won’t know what the ingredient consists of. We wrote an article at Formula Botanica this week on how to spot a fake hydrosol which has made some waves in our skincare formulation community, because you just don’t know what you might be buying unless you can fully trust your supplier."

And what if you’re seeking natural formulas? “You won’t be able to tell from your ingredients list if your ingredient is animal-derived, vegetable-derived or lab synthesised,” warns Lorraine. "Many natural preservatives often end up being synthesised in a lab - they have exactly the same chemical structure and function as their natural counterpart but it’s cheaper to manufacture them in bulk in a lab.”

And don’t be fooled into thinking organic is any clearer

"The labelling requirements are exactly the same for organic and synthetic formulations, which means that you don’t always know where the ingredient came from, what it consists of and how it’s been treated before it was added to your formulation,” confirms Lorraine.

How many ingredients are easy to recognise?

Not many. I always look for MI, SLS and ‘parfum’ as a matter of course, as well as chemical sun screen ingredients  which I prefer to avoid - but aside from looking ingredients up individually, it’s hard to spot something and know exactly what it is.

Lorraine agrees. “Although there are always general rules of thumb when it comes to chemical names, it is best not to try to look for patterns. A good example is cetyl alcohol which is a fatty alcohol used in cosmetics as a thickener, emulsifier and emollient. Consumers sometimes think this is the same as alcohol, which is a completely different chemical!”

If you don’t speak the chemical lingo, can you look them up?

“The best place to look up cosmetic ingredients to find out what they are is the CosIng database , managed by the European Commission,” advises Lorraine.

Want to get your geek on? Lorraine recommends Milady’s Skin Care and Cosmetic Ingredients Dictionary  for finding more scientific information about the ingredients.

So how can you judge a product’s safety for sensitive skin?

A product's INCI list is certainly too simplistic to answer that; after all, a label not only won't tell you the quality of what’s been used, but it also won’t give you a clear indication of how much is in there - and concentration is key in sensitive skin. An ingredient might be considered an irritant in its purest form, but at 0.1 per cent it may be harmless.

Lorraine (and many other skin experts in my previous columns) recommends going for simpler formulas, with fewer ingredients, so that if you are prone to reactions it’s far easier to work out what’s caused it. “That way you’ll find it much easier to eliminate any ingredients that are causing you problems. Rather than purchasing a facial oil that contains a blend of 30 carrier oils and essential oils, I recommend trying out a single carrier oil on its own instead.” Choose less complex formulas and then patch test it carefully  - you can than gradually try skincare with more ingredients to see what your skin can and can't deal with.

An INCI list is a great place to start, given that it’s a universal classification system, but for those of us who are sensitive, there's more research to be done. “Ultimately,” concludes Lorraine, “it will come down to the amount of trust you have in the formulator and manufacturer of the product you’re buying.”

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