There's a decision you make every single morning without thinking about it, and it spends the whole day pressed right up against you. It's the fabric of your underwear. Most guys inherit that choice from whatever their mom bought them in high school and never revisit it. So we revisited it — out loud, on camera, with samples in hand. Here's what four fabrics are actually doing down there, and how to stop picking the wrong one.
Cotton: The Friend Who Overstays His Welcome
Cotton is natural, breathable, and has been in underwear since the Jockey days for good reason. It absorbs sweat, it's versatile, it's comfortable for casual wear. The problem is what happens after it absorbs that sweat: it just holds it. Cotton can soak up to 27 times its weight in water, pulling liquid straight into its core like a sponge and then sitting there with it. Add the fact that cotton can't be woven as thin, and you get a bigger, rougher weave that chafes — sometimes leaving salt deposits behind that make it worse.
The fix isn't necessarily ditching cotton; it's checking the weave. When we put a Hanes pair next to a Calvin Klein Icon pair, the difference was obvious up close. That thick, abrasive Hanes weave was the exact thing that had Chris itching in class years ago. A tighter, finer weave — think Pima-grade cotton — is a completely different experience.
Modal: The Luxurious One
Modal (or “modal,” depending on who you ask) is a semi-synthetic fiber made from reconstituted beech pulp, and its calling card is softness. It absorbs about 50% more moisture than standard cotton, but unlike cotton it actually wicks — it releases moisture and dries faster. We've worn modal boxer briefs for real heavy labor, lifting logs and mowing in 100-degree heat with matching humidity, and it holds up, especially when the cut keeps your skin from rubbing skin.
It keeps its shape wash after wash, stays soft, and doesn't shrink into a smaller, sadder version of itself the way cotton does. The one quirk: over time you might see a few fabric pills on the outside. Small price for that feel.
Nylon: The Quiet MVP
Nylon — sometimes labeled polyamide, so watch for that on the tag — is where durability and hot-weather comfort meet. It's hydrophobic, absorbing only about 4% of its weight in water, so it never gets heavy, and it wicks beautifully; give it a little breeze and it clears out fast. It's got great spring-back, which means it stays put when you're walking or running and keeps your thighs from arguing with each other.
It's also the undisputed travel champion: rinse a pair in the hotel sink at night, park it in front of the AC, and it's dry by morning (a blow dryer works in a real emergency). Here's the tell that separates it from its evil twin: nylon feels cool to the touch. Polyester feels warm.
The Takeaway
If you remember one thing, remember this: don't buy polyester underwear. Untreated polyester traps heat and bonds with your body oils, building a permanent home for odor-causing bacteria — that's why the same locker-room smell keeps coming back no matter what you eat or how little you sweat. The good news is the cost gap between polyester and nylon is small these days, so there's almost no reason to settle.
If you want natural, get a tight-weave cotton or modal. If you want synthetic, get nylon. And if you want the version that actually separates and supports instead of just wrapping you in a fancy loincloth, that's the whole reason Real Men Apparel exists. Try the pouch once and you'll understand why we get this excited about underwear.
Real Men - Real Talk is a weekly show from Real Men Apparel. Watch the full fabric deep dive →
