The Best Underwear Material for Sensitive Skin — and How to Read a Fabric Label | Cuurve

The best underwear material for sensitive skin — and how to read a fabric label 

If your skin reacts to most underwear, the answer is usually in the fabric label 

Most of us have a label in our underwear that we never read. It sits at the back, slightly scratchy, usually cut off at some point. But that label tells you something important: what percentage of what fabric is in direct contact with your most sensitive skin, all day and all night. 

I started reading labels because I had to. I have macular amyloidosis — a skin condition that causes constant, relentless itching. For years, I could not find underwear that did not make it worse. Seams that scratched. Lace that irritated. Fabrics that trapped heat and made my skin flare. I tried everything. Most of it failed. 

Eventually I stopped looking for the right product and started understanding why nothing worked. The answer was almost always in the fabric composition. That is what this post is about. 

How to read a fabric composition label 

By law in the UK, every garment must display its fibre content as a percentage. You will see something like: 95% modal, 5% elastane. Or: 80% polyester, 15% nylon, 5% elastane. 

That first number matters most. It tells you what the majority of the fabric is made from — and therefore what sits against your skin for the most hours of the day. 

For most high-street underwear, that first number will be polyester or nylon. Both are synthetic fibres derived from petrochemicals, not natural sources. They do not breathe in the same way natural or natural-derived fibres do. For women with sensitive skin, reactive conditions, or bodies that run hot, this is where the problem starts. 

Synthetic vs natural-derived fibres — what the difference actually feels like 

Synthetic fibres like polyester trap moisture against the skin. They do not absorb it and release it — they hold it. For most people, most of the time, this is an inconvenience. For women with skin conditions, hormonal sensitivity, or who are navigating perimenopause and experiencing night sweats, it becomes a problem that disrupts sleep and aggravates skin. 

The best underwear material for sensitive skin is one that moves moisture away from the body, does not create friction, and breathes. The fibre that consistently meets all three criteria is TENCEL™ Modal. 

TENCEL™ Modal is derived from sustainably sourced beech tree pulp and produced by the Austrian company Lenzing AG using a closed-loop process that recycles water and solvents. It is not the same as generic modal or viscose. The Lenzing certification means the fibre meets verified environmental and performance standards.
Against your skin, it is: 

•  breathable and moisture-wicking, absorbing moisture more efficiently than cotton and releasing it into the air rather than holding it against the skin
• hypoallergenic, with a smooth fibre surface that reduces friction and irritation
• temperature-regulating, which matters particularly at night
• soft in a way that does not deteriorate quickly with washing 

If you are looking for underwear that doesn't cause irritation, the fabric composition is the first place to look — before the brand, before the price, before the style. 

Why fabric composition affects sleep — especially in the second half of your cycle 

I notice this most clearly in the week before my period. My body runs hotter. I wake up in the night uncomfortable, skin sensitive, temperature spiking. It took me a while to connect this to what I was sleeping in — but once I did, it became obvious. 

Polyester does not help you cool down. It does not let moisture move away from your body. TENCEL™ Modal does both. The difference in quality of sleep is not subtle. 

This is also relevant for women in perimenopause. Hot flushes and night sweats are not just uncomfortable — they are exhausting. The fabric you wear to bed either helps your body regulate temperature or it works against it. Synthetic fabrics actively work against you. Natural-derived fibres, particularly those with strong moisture-wicking properties, give your body a better chance. 

Is modal good for underwear? what dermatologists say 

This is one of the most common questions we see from women researching fabric for sensitive skin. The short answer is yes — with a caveat. 

Modal is a broad category. Not all modal is the same. Generic modal and viscose can be processed using methods that leave chemical residues in the fabric. TENCEL™ Modal specifically uses a closed-loop, non-toxic solvent process, which means no harmful residues remain in the finished fabric. This is the distinction that matters for sensitive skin. 

For a more detailed look at what skin specialists look for in underwear fabrics, read our post on what underwear dermatologists recommend. 

What to look for on the label 

You do not need to become a fabric expert. But the next time you buy underwear — or the next time something is making your skin uncomfortable — check the label first. 

Look for a high percentage (80% or above) of one of the following in the main fabric: 

•  TENCEL™ Modal or modal (derived from beech wood pulp, breathable, smooth, moisture-wicking; TENCEL™ certified is the higher standard)
• cotton (natural and breathable, though less moisture-wicking than modal)
• bamboo (natural and antibacterial, though processing methods vary — check whether it is mechanically or chemically processed) 

A small percentage of elastane (typically 5–8%) is normal and necessary for stretch and shape retention. What to watch is the primary fibre — especially if your skin reacts, you sleep hot, or you are navigating a condition that makes your body more sensitive than usual. 

Why Cuurve is built around this 

Every Cuurve piece uses TENCEL™ Modal as the primary fabric — sourced and verified directly with Lenzing. The gusset on every piece uses bamboo, which is natural and antibacterial. The stretch lace is chosen because it gives rather than grips. 

I test every piece on my own body before it reaches yours. With macular amyloidosis, my skin tells me immediately if something is wrong. If it passes on me, it is genuinely soft. That is not a marketing line — it is the only quality control that actually matters to me. 

You deserve to know what is touching your skin. Start with the label. 

— Aileen, founder of Cuurve