Now that autumn is here, the high street is flooded with cosy jumpers, warm coats and sturdy boots. The labels tell us they are “Wool Blend”, “Cashmere-Rich”, “Recycled Polyester”…. but what does that actually mean and is that good or bad?

So why should we care about the fabric content?

The fibre content is key to how the garment will function and if it is fit for purpose. For example, natural fibres are fantastic at regulating our temperature. Synthetics fibres are great for adding stretch to a fabric or for sportswear. Used incorrectly, you end up with garments that are not fit for purpose e.g. acrylic jumpers sometimes don’t feel warm but can also make you sweaty!  

Our high street shops are using more and more blended fibres in a bid to, if I’m feeling generous, get the best of both man-made and natural fibres and, if I’m not, just to reduce costs. 

Even the solid high-street shop, M&S, is shadowing their Planet A credentials by creating fibre-mixes with more synthetics than natural materials. Why is this problematic?…

Firstly, let’s think about the types of fibres used in clothes; we have 2 main categories – natural and synthetic (man-made).

Natural fibres- cotton, wool, linen, satin, bamboo. On the plus side, they are breathable, they keep us warm in the cold and cool in the heat (think warm woolly jumpers and cool linen trousers. These fibres are easily dyed, although the colour can fade. They are more expensive to produce than synthetics and can stretch out of shape whilst wearing. 

Synthetic fibres- polyester, acrylic, nylon, elastane. No two ways about it – they are made of plastic. They wrinkle less than natural fibres, are more affordable to produce, are lightweight and can be water resistant (think sportswear and raincoats). However, because they are made from plastic they are difficult to recycle or take hundreds of years to biodegrade.  Micro-plastics from washing these garments are ending up in our soil, our oceans and, sometimes, our food. Synthetic fibres can also hold onto smells which is not great when they also don’t help to regulate your temperature – cue smelly armpits!

[Viscose is the odd one out as it can be considered natural or synthetic. Although it’s made from wood pulp, the industrial process to turn it into fabric is so intensive that it could be considered synthetic.]

Why do we mix fibres?

Manufacturers want to get the best qualities from both fibres i.e. a poly-cotton shirt requires less ironing than a 100% cotton one and is cheaper to make. Cotton and polyester also make great sportswear – comfortable and moisture-wicking. Wool-acrylic blends can be easier to care for and retain their shape but the main reason for using them is to reduce costs.

What’s the problem with mixing synthetic and natural fibres? 

Natural and synthetics fibres have very different properties. After being woven together, they are fighting against each other, when the fabric is rubbed they want to break away from each other i.e. bobbling or pilling after friction movement or being washing etc.  

Once fibres are mixed, they are nearly impossible to recycle as different methods are needed for the different fibres causing a big disposal problem.

The more complex the combination of fibres, the more of the negative attributes tend to be seen. For example, a jumper with over 50% synthetics to wool will have that plastic-y sheen to it and won’t have the warmth and breathability properties of the wool. It will also bobble badly!

What should we be doing?

Steering clear of blended fabrics is difficult and I am not here to tell you that you shouldn’t buy them or, worse, get rid of those in your wardrobe.  

So, here are my top tips: 

• Look after the clothes you already own by only washing them when absolutely necessary. Just spot cleaning or airing can do wonders!
• Invest in a good de-bobbler! I have a Philips one, you can find lots of options on eBay Philips Fabric Shaver for sale | eBay
• Check the fabric label – Look for fabrics that contain 1 or 2 fibres, rather than 3-4 
• If you want the properties of natural fibre, make sure it’s over 90% natural.
• When buying something, try looking for natural options – secondhand is a great place to start – try Nearly New Cashmere Co. or searching “100% cotton” on Vinted or other resell platforms

Beware that brands are marketing their blends “Cotton-rich”, “Merino-wool blend”, “Recycled polyester” etc. as as positive (green-washing? Perhaps!). Now you understand the qualities of both natural and synthetic fibres, you can check the fabric labels yourself and make your own, informed decisions.