Men’s fertility has dropped 50% in 50 years: let's talk about men's underwear

Photo by Cosmin Ursea on Unsplash

Most men do not think twice about their underwear, however its time they start paying attention (ladies if you are reading this make sure you make the change for them or tell them why and how!)

Why Polyester Underwear Is a Problem

Conventional men’s underwear is almost universally made from polyester — which is plastic. And like all plastics, it doesn’t just sit inertly on your body. It leaches chemicals, sheds microplastics, and traps heat in all the wrong places.

There are a couple of ways plastic underwear can affect male health:

1. Heat: Healthy sperm production requires the testes to stay 2–4°F cooler than core body temperature. Polyester traps heat. In a landmark human study, men wearing polyester scrotal support became azoospermic — this means producing zero sperm — within an average of 140 days. Their fertility returned when they stopped using the polyester underwear.

2. The microplastic problem: A 2025 study detected microplastics in 34 out of 45 human semen samples, averaging 17 particles per gram of semen. Men with PET plastic (the exact polymer in polyester clothing) in their semen showed lower progressive sperm motility. A 2024 study across 113 men found microplastics in every single semen sample — and each additional plastic type correlated with lower sperm count and motility. Underwear is not the only source of microplastics but it is the main source for microplastics in semen

3. The chemical problem: Polyester fabrics routinely contain antimony (an estrogen-mimicking heavy metal used in 80–85% of polyester manufacturing), phthalates, and BPA — all of which can migrate out through sweat and skin contact. Underwear worn for hours against thin, sensitive skin is arguably the worst place to have these chemicals.

The fix is simple: swap to natural fibers. GOTS certified organic cotton and/ or responsible wool are great options. Here’s where to start.

The Brands Worth Knowing (in no particular order)

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🌿 PACT

*Best for: The everyday swap, budget-friendly*

The easiest entry point into non-toxic underwear. Made from GOTS-certified organic cotton in Fair Trade Certified factories, with non-toxic dyes and no synthetic coatings. Soft, reliable, and affordable enough to replace your entire drawer at once.

• Products: Boxer briefs, boxers, briefs, trunks

• Price per pair: $18

• Certifications:** GOTS, Fair Trade USA

🌿 OPOK (discount code: aidaspicks)

Best for: Clean and minimal*

A straightforward organic cotton option with honest certifications and a no-fuss approach to design. Good mid-range pricing for a single pair.

• Products:** Organic boxer briefs

• Price per pair:** $28

• Certifications:** GOTS

🌿 SUBSET

Best for: Modern organic basics*

Subset takes a clean-label approach to men’s basics — organic cotton underwear that prioritizes both material safety and modern fit. Mid-range price for a quality single pair.

Products:Organic cotton boxer briefs

Price per pair:$26

Certifications: GOTS

🌿 Q FOR QUINN

Best for: Premium organic with full certification*

One of the most thoroughly certified brands on this list — GOTS and OEKO-TEX across the board. Clean knit construction, available in a range of colors. Worth the price for anyone who wants full third-party verification from seed to seam.

• Products: Everyday knit boxers

• Price per pair: $37

• Certifications:GOTS, OEKO-TEX

🌿 ORGANIC BASICS

Best for: Stocking up without breaking the bank*

Ethically made in Europe from long-staple GOTS organic cotton and TENCEL. Clean, minimal design in a range of solid colors. Great value when bought in multi-packs — some of the best per-pair pricing on this list.

• Products: Core Trunks (3-pack), Boxer Briefs (3-pack)

• Price per pair:** ~$17.66 (trunks) / ~$18.66 (boxer briefs)

• Certifications:** GOTS, OEKO-TEX, PETA Vegan

🌿 JOCKEY

*Best for: The familiar brand upgrade*.

A mainstream brand most men already trust — and their organic cotton stretch line is a legitimate non-toxic option at an accessible price point. Not as deeply certified as some brands here, but a good gateway for anyone not ready to go full non-toxic niche.

• Products:Organic cotton stretch 4” trunks (3-pack)

• Price per pair: $12

• Certifications:** Organic cotton (certification level varies by style)

12 more options at all price points below for subscribers~!

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