For summer, MicroModal and Lyocell are the strongest choices. Both are naturally derived, breathe better than cotton, and stay drier than synthetics. Lightweight cotton is a reasonable backup. Polyester and nylon trap heat and hold odor longer in warm conditions.
Summer puts underwear to a real test. Heat builds, sweat accumulates, and most fabrics that feel fine in March become uncomfortable by July. The difference between a good day and a miserable one often comes down to what's closest to your skin.
How the main fabrics actually perform in heat
Not all breathable claims are equal. Here's how the common options stack up on the things that matter most in warm weather: moisture handling, drying speed, and how they feel after a few hours.
| Fabric | Moisture wicking | Drying speed | Feel after hours of wear |
|---|---|---|---|
| MicroModal | Strong | Fast | Soft, stays dry |
| Lyocell (TENCEL) | Strong | Fast | Smooth, cool to touch |
| Cotton (standard) | Moderate | Slow | Heavy when wet |
| Polyester | Fast initially | Fast | Traps heat, holds odor |
| Nylon | Moderate | Moderate | Warmer than it looks |
Peer-reviewed comparisons of eco-friendly apparel fibers confirm that naturally derived materials like Lyocell perform well on sensory comfort and moisture behavior relative to conventional alternatives. [1] Cotton and nylon comparisons show synthetics lag on comfort-related transmission properties in warm, humid conditions. [2]
Fit matters as much as fabric
A looser cut allows airflow that a compression fit blocks entirely, regardless of what the fabric is. If the underwear is gripping tightly, even the best material can't compensate. For summer, a slightly relaxed brief or a longer cut that doesn't bind gives the fabric room to do its job.
- Avoid tight waistbands that sit high and seal in heat around the midsection.
- Skip compression fits unless you're actively training and changing afterward.
- Prioritize flat seams so there's no friction point when you're already warm and moving.
The area that needs to stay cool benefits from both: a fabric that moves moisture and a cut that doesn't press everything together. One without the other is a partial solution.
Oakman launches Fall 2026. Founding members get first access and founding pricing locked in. Reserve your spot.
Where Oakman fits into a summer wardrobe
Oakman is built specifically for active men looking for scrotal cooling all day and want the option of a cold pack for cooling in the sauna or after heat exposure. The fabric is TENCEL MicroModal, naturally derived from wood pulp rather than plastic, blended with ROICA V550, a clean Japanese stretch fiber, rather than conventional spandex. The fit is athletic with a gusset, an extra panel that gives the testicles room and airflow. Dyes are bluesign approved, so what touches your skin is controlled all the way through the supply chain. If you're spending summer days in heat, whether that's outdoor work, a gym routine, or regular sauna sessions, the daily layer is worth getting right. Oakman launches Fall 2026, and the Founding 100 get first access.
Related reading
Related reading
- When Is the Best Time of Day to Use a Sauna for Sleep Benefits?
- Best Materials for a Durable, Efficient DIY Sauna
- Best Breathable Underwear For Men
- Best Cooling Underwear For Men
- Best Alternative To Cotton Boxers
Frequently asked questions
Is cotton good for men's underwear in summer?
Standard cotton absorbs moisture well but dries slowly, which means it can feel heavy and damp after a few hours in heat. Lightweight or combed cotton is better than a thick weave, but naturally derived fibers like MicroModal and Lyocell outperform it on drying speed and sustained comfort.
Why do synthetics feel uncomfortable in hot weather?
Polyester and nylon move moisture quickly at first but tend to trap heat against the skin and hold odor after extended wear. In cool or moderate conditions they're fine, but in summer heat the thermal buildup becomes noticeable within a few hours.
Does underwear fit affect how cool you stay in summer?
Yes. A tight or compressive fit reduces airflow regardless of fabric. A slightly relaxed cut lets air circulate and gives moisture-wicking fabrics room to work. Fit and fabric work together, and neither fully compensates for a poor choice in the other.
What does bluesign approved dye mean for underwear?
bluesign approval applies to the dye supplier and production process, meaning the dyes meet defined standards for how they're made and used. It's a sourcing credential, not a health guarantee, but it does mean the materials going into the garment are tracked more carefully than most conventional underwear.
