Know Your Fibers: Natural, Synthetic or Semi-synthetic

When it comes to fibers, we are going way beyond colors and style – we are talking about the nature of the texture, how it falls around your body, how it feels on your skin, how it is produced, and last but not least, if it is sustainable. Sustainability in fashion means for us to look deeper, starting from the seed, going through its processing until it becomes a fabric, and ending where the garments end – in the landfill.

Fibers can be divided into three groups – natural, synthetic, and semi-synthetic. Natural fibers are made and designed by mother nature: a plant, an insect, or an animal. Synthetic fibers are mostly petroleum-based, completely man-made, and generally not very sustainable. Semi-synthetic fibers are both – they have a natural base (cellulose) which is treated chemically to become a textile fiber.

We are not trying to put a label on the clothes (although reading the labels is always a good idea), we are just trying to get deep into the nature of what we wear. So, let us take you on a journey and dive into the world of fibers.

	Natural	Synthetic	Semi-synthetic
Origin	Plant, Animal	Petroleum-based	Tree, Bamboo
Examples	Cotton, Hemp, Linen, Silk, Wool	Polyester, Nylon, Spandex, Acrylic	Viscose, Bamboo, Modal, Lyocell, Cupro
Best For	Everyday clothing, Underwear, Sleepwear, Linens	Activewear, Outerwear	Everyday clothing, Underwear, Sleepwear, Linens
Durability	Medium-strong, not too stretchy, may shrink	Strong, doesn’t stretch or shrink	Medium to low, some rayons may stretch
Comfort	Breathable, soft, cozy	Non-breathable, light	Mostly breathable, soft, cozy
Aesthetics	Versatile, colors tent to fade faster	Drapes well around the body, shape fitting, retains color	Drapes well around the body, retains color
Sweat & Heat Management	Breathable, water-absorbent (NOT good for performance and extreme weather)	Thermostatic, low water absorption (Great for performance and extreme weather)	Mostly breathable and absorbent
Maintenance	Need ironing, low washing temperatures, slow drying	No creasing, fast drying, stain-resistant	Needs ironing, low washing temperatures, slow drying
Biodegradable	YES	NO	YES
Environmental Impact	Water and/or carbon-intensive, may affect the biodiversity, cause land degradation, pollute water, and hurt animals	Made of non-renewable fossil fuels (petroleum), high CO₂-eq emissions, high energy demand	May lead to deforestation and leak chemicals that harm nature, people, and animals
Eco-friendly Options	Organic Cotton / Hemp / Linen, Recycled Wool	Recycled Polyester / Nylon	ECOVERO™, TENCEL™
Certificates	GOTS, OEKO-TEX®, OCS	GRS, OEKO-TEX®, Bluesign®	FSC, PEFC

Natural Fibers

Cotton, linen, hemp, silk, wool – they are all fibers that naturally occur. Natural fibers grow mostly from plants but not only – silk, for example, is produced by insects, woven into a cocoon; wool is also “grown” on animals. If you are vegan, you might want to take into consideration the animal origin of silk and wool. And while many people think that “natural” means “good”, we need to read between the lines. Plants, when grown industriously, are treated heavily to guarantee high yields. Some of them also need great amounts of water and resources to grow.

Cotton

Soft, breathable, and practical – cotton is a great choice for any season. It is completely biodegradable and will disappear from the land-fill completely if the cotton fibers aren’t woven with synthetic ones. Cotton is a beautiful plant that, however, takes a lot of water to grow. So much water that the Aral Sea is only a tenth of its original size – it is so heavily used for irrigation purposes. To make it more graphic, let’s say that a cotton shirt takes around 2700 liters to make. Apart from that, like every industrially grown plant, manufacturers use a load of insecticides and pesticides to help cotton survive until it’s picked – they cause a lot of health issues to people who work directly on the field and also to those weaving the cotton threads. These chemicals are also detrimental to biodiversity and soil.

Wool

If you want to keep warm, wool is a great choice – it is a natural fabric, made from the coats of sheep. It is breathable, makes us sweat less, and doesn’t let bacteria grow. When it comes to mass production, however, there are some things we need to be on the lookout for. In the first place, there are some vegan considerations – sheep, bred for their wool, are often severely treated and harmed in the process of shearing. Raising sheep isn’t very sustainable either – it is responsible for high levels of greenhouse gas emissions (sheep are the second-largest group of methane-emitting livestock after cows); it is also accountable for water pollution near farms. On the bright side, wool is biodegradable so it won’t stay in nature forever if the fabric isn’t treated heavily with chemicals and dyes.

Linen

Let us present you “good guy” linen – the fiber derived from the flax plant. It is naturally moth-resistant, it is very breathable and absorbent without holding bacteria making it ideal for the hot summer weather. It is a very durable fabric that gets softer over time so if not stained or damaged otherwise, it can last you a long time so it is not exactly “fast fashion”. Linen crops are not as thirsty as cotton and the really good news is that it takes only 6,4 liters of water to create a linen shirt. Good news number two: one hectare of flax retains 3,7 tons of CO2 (according to the European Confederation of Linen and Hemp). Do you remember how much water a cotton shirt takes? The difference is substantial. If you choose a linen garment, let it be a natural color one (they vary from grey to light brown), otherwise, it has gone through a heavy bleaching process. The fabric, when it is natural pure linen, is completely biodegradable (and also fast – it starts to decompose in just 14 days).

Synthetic Fibers

After we saw what nature can make, it is time to look at man-made fabrics. Synthetic fibers are petroleum-based and are mostly non-biodegradable. Recycling them is expensive and difficult. And it can take up to 200 years for a synthetic shirt to decompose so once they get into a landfill, they create a long-term pollution problem.

Synthetic materials, on the other hand, are cheaper and a lot more durable, they don’t get easily wrinkled or stained. They can be designed to be waterproof and as a whole – weatherproof, which makes synthetic clothes good for outdoor and sports. Some of the most common synthetic fibers are polyester, nylon, spandex, acrylic.

Polyester

This is the most used synthetic fiber - around 60% of all fibers. Polyester is cheap, doesn’t crease, and can be washed at low temperatures. It is made of petroleum residues and takes a lot of energy to be processed and pollutes the air and water. It is not breathable and thus retains temperature which makes us sweat more. When washed, clothes made from this synthetic material shed plastic microparticles that are dangerous to marine life. And while polyester is durable and you can therefore use it for a long time, it is a material that will last forever when it ends up in a landfill – its decomposition takes from 20 to 200 years so it creates a serious pollution matter. Some companies are starting to use recycled plastic bottles to produce polyester clothes. Take a more detailed look at polyester and find out how sustainable it is.

Nylon

Patented in the 1930s, nylon is another synthetic fiber that is derived from petroleum. It is stretchy so when it comes to clothing, it is mainly used for stockings, socks, swimwear, lingerie, and activewear. Clothes made from nylon are light, fast-drying, and, just like polyester, hold temperature in, so we would better use them when it’s cold. But these otherwise handy garments come at a price – this material doesn’t biodegrade and remains in landfills for hundreds of years. To manufacture nylon, a large amount of water is needed. During the process a gas called nitrous oxide is released – this gas is 300 times more polluting than carbon dioxide. The energy needed for the process is also high so this is another downside of this fiber. More about nylon you can find in our guide to sustainable nylon.

Spandex

Spandex is also known as elastane and is also known by its brand name LYCRA (we didn’t lose you, did we – spandex, elastane and LYCRA are the same thing). It is a stretchy material made from a polyester or nylon base. Leggings, bikini, tights, and other skin-tight clothes are made of spandex so if you are an athlete, for example, you can take advantage of this fabric as it allows you to enjoy the freedom of motion. Just like polyester and nylon, it takes a lot of energy to produce; it’s a chemical-heavy process and the dyes used are also a cause of most pollution when it comes to elastane. It is not biodegradable and you wouldn’t want it to end up somewhere in nature – it will last a long time there.

Semi-synthetic Fibers

Semi-synthetic or cellulosic fibers are derived from renewable materials you find in nature (the most common one being wood pulp) that were dissolved by using chemicals and then regenerated. The newly-made fibers are woven into fabrics just like the rest. Examples of such fibers are viscose, modal, and lyocell.

Beware that many mass-produced semi-synthetic fibers get their cellulose from rainforest areas where deforestation has become a major issue for the local ecosystems, wildlife, and indigenous people. In addition, the manufacturing process can be very toxic to the environment and people living and working near rayon factories.

Viscose

Viscose has been around for more than 100 years and is the first man-made fiber, initially invented to replicate silk. It is lustrous, drapes nicely, and feels soft and smooth on the skin – a mixture between cotton and silk. Being a delicate fiber, it is prone to stretching which makes it hard to maintain and NOT a very lasting one. Viscose is usually made of wood pulp from a variety of fast-growing trees, and more recently even from bamboo. Turning pulp into viscose is known as the rayon process - a series of chemically-intensive interventions to dissolve pulp and regenerate it into a fiber. Manufacturers use carbon disulfide, caustic soda, and sulfuric acid which makes the process of producing viscose fibers harmful to both the environment and the people in and around factories.

Modal

Made from softwood trees, modal is another man-made fiber. It is smooth, breathable, and water-absorbent. It has superior durability compared to viscose and is generally considered low-maintenance. It doesn't crease or shrink and is not prone to pilling. Much like viscose, modal is chemically produced but it uses fewer substances and therefore the process is not as toxic. Additionally, a lot of manufacturers have already adopted a more environmental chemical management that captures hazardous waste before it gets discharged.

Lyocell

Lyocell has been around for nearly 30 which makes it the latest rayon technology. Similar to other rayons, lyocell is breathable, odor-resistant, and absorbent. It is very soft, drapes well, and feels smooth on the skin. Unlike viscose, it doesn`t use carbon disulfide in manufacturing which makes it safer for people, animals, and the environment. It is made in a closed-loop process using an organic solvent (amine oxide) which not only prevents harmful chemicals to leak into the environment but also recovers and reuses more than 99% of the solvent.

Instead of Conclusion

No matter what piece of clothing we decide to invest in, it will certainly have some impact on the planet. However, bits of awareness can make us feel better about how we look both from the inside and out by choosing fashion that protects nature, people, or our skin. Choose clothes you need (if you buy a new tracksuit, be sure you start jogging) or clothes you really like (and not might-wear-it-someday ones). And if you notice that a garment hasn't left your wardrobe in a long time, why not give it as a present to a friend that will appreciate it? Be mindful and enjoy life in clothes that save the world.