What is Microfiber (And Do You Want it in Your Cloth Diapers)?

By April Duffy •  Updated: 05/27/24 •  7 min read

Microfiber inserts for cloth diapers are everywhere. They come with every discount pocket diaper around and are sold on their own as well. Microfiber is sold in white, multi-layer microfiber inserts, and are even hidden inside grey “bamboo charcoal” inserts as well. But if you’ve spent any amount of time in the cloth diaper community groups, you will have noticed a lot of people hate on microfiber.

So what’s the deal with microfiber, and do you want it in your cloth diapers? Microfiber (or microfibre) is a synthetic fabric made from polyesters and polyamides, or a conjugation of polyester, polyamide, and polypropylene. In other words, it’s made from plastics. These plastic fibers are 100 times finer than human hair and densely packed to make absorbent cloths.

Microfiber diaper inserts are
quick absorbing and cheap, but there are many more cons to microfiber than pros, and those that know them all often prefer other types of cloth diaper inserts over microfiber.

Note: Microfiber should not be confused with microfleece. You can learn about the differences between those two fabrics here.

The problems for microfiber are many, including its environmental impact, its irritation of the skin, and the fact that natural fibers work better for most diaper situations.

Let’s take a look at each of those.

Why is Microfiber so Bad for the Environment?

The environmental problems with microfiber stem right from its basic makeup. Since it’s made from plastics (petroleum-based) it’s less desired right from the start for many health and eco-conscious parents. However, it’s those super-thin fibers it’s made from that are possibly a bigger problem, environmentally speaking.

But let’s rest our eyes for a minute and watch a cute video by The Story of Stuff Project that explains it all:

Wow, right? So no only does synthetic material like microfiber dump micro-plastics into the ocean, but those micro-plastics are slowly poisoning the sea life many of use then consume, putting that plastic and contamination right into our bodies (and the bodies of our littles)!

Just how much microfibres are being released into the oceans? While I wasn’t able to find anything specific to diaper inserts, this 2018 study by Metropolia University of Applied Sciences looked at synthetic jackets, which also release microfibers into the water (like microfiber inserts).

That study said that if 100000 synthetic jackets are washed, the total weight of the microfiber (average for old and new garments) was 1.5 grams. This means that if 100000 synthetic jackets are washed, 150 kg of microfiber is collected. Of that, 15% of the microfiber is released to local water bodies after washing. The amount of microfiber released in the ocean would be 22.5 kg, which is equivalent to 4090 plastic grocery bags.

That’s insane!

Finally, Plastic doesn’t biodegrade. Just like the disposable diapers your friend uses, your microfiber inserts will be around long after you aren’t.

Why is Microfiber Irritating to Skin?

Whether or not you’re concerned with the environmental damage caused by microfiber, you need to know that microfiber can not be placed next to your baby’s skin in a diaper.

The problem is that all those tiny fibes in microfiber are so absorbent, that they actually will suck moisture out of the skin causing irritation and rashes if left there for any length of time.

Placing another piece of fabric between the microfiber and baby is all that’s required to keep it from irritating the skin, which is why the inside liner layer of a pocket diaper works so well with microfiber. If for some reason you don’t want to put the insert into the pocket, or want to use it with a cloth diaper cover, you can use a fleece cloth diaper liner for this.

Microfiber vs. Bamboo, Hemp and Cotton Diaper Inserts

Many ask me, which is better microfiber or natural fibes like bamboo, hemp or cotton? As we read above, natural fibers are better environmentally since they are not dumping tons of microplastics in the ocean and will eventually biodegrade, but for those that don’t care about that, they just want the best diaper inserts, which is better?

Well, microfiber has some pros, and many cons when compared to natural fibres, let’s take a look at each area to compare them:

Click here for a printable PDF of the cheat sheet.

Cost (Microfiber Wins)

Since microfiber is synthetic, it is significantly cheaper than natural fibers like bamboo, hemp, and cotton.

How Fast It Absorbs (Microfiber Wins)

Microfiber is actually the fastest absorbing fabric offered in a cloth diaper insert. Put another way, it sucks the wetness into the fabric the fastest. If you have a baby that “floods” the diaper, this makes layering in a microfiber insert into your diaper insert stack a great idea.

Compression Leaks (Microfiber Loses)

Unfortunately, though microfiber is made to quickly absorb, it’s also made to be wrung out and used again, which means it easily leaks when pressure is put onto it. You’ll hear these leaks called cloth diaper compression leaks.

When your baby is sitting for long periods of time in the same position (car rides, high chair, swing, etc.) the compression of their weight and any straps keeping them in will likely cause a compression leak with microfiber inserts.

Absorbency Amount (Microfiber Loses)

Microfiber is great for absorbing quickly. And it can hold a lot, but natural fibers like hemp, cotton, bamboo can hold a ton more with the same number of layers.

Bulk (Microfiber Loses)

Microfiber is one of the bulkiest inserts around, especially when part of a Bamboo/Charcoal insert.

If you have a heavy wetter and need more than one insert the size of combining multiple microfiber inserts can quickly lead to “overstuffing,” which is when the thickness of the inserts is so much that it pushes the diaper’s elastics out of baby’s leg creases, which can cause leaks. Overstuffing can also create. compression leaks.

Build-up Causing Smells and Rashes Over Time (Microfiber Loses)

It’s well known in the diaper community that microfiber inserts will start to smell long before your natural fibers do, but why?

Well, those tiny, densely packed fibers that create microfiber in the first place mean that microfiber also doesn’t wash as clean as natural fibers, especially on a bacterial level. By having so many tiny fibers tightly packed in, you in effect have billions or trillions of tiny hiding places for detergent, dirt, and bacteria to hide.

Have you ever noticed how hard it is to get a piece of lint off of a microfiber insert? Well, think about that urine bacteria deep in the inner layers of that microfiber insert, inside layer upon layer of teeny-tiny fiber loops. It’s no wonder microfiber is so much harder to keep clean and fresh vs. smoother, larger, natural fiber weaves.

Aside: Some microfiber manufacturers claim that microfiber is anti-bacterial in nature, speaking specifically about cleaning bacteria off surfaces. But studies like this one from done by the Association for Professionals in Infection Control and Epidemiology in 2010, show that microfiber isn’t as effective at cleaning microbial loads from surfaces as cotton after it’s been washed several times.

Next Steps

If you’re still not decided on microfiber, I have a post giving the run-down on all the insert types along with the help you need to choose, you can check out that post here.

And don’t forget to print the Insert Absorbency Checklist by clicking on the image to open the PDF:

Click here for a printable PDF of the cheat sheet.

April Duffy

April is the founder of Cloth Diapers for Beginners and author of The Cloth Diaper Wash & Care Handbook. Since 2015, April has helped well over 75,000 parents and caregivers cloth diaper their children through this website, her book, her YouTube Channel, and the Cloth Diapers for Beginners Facebook Group.