We get this question a lot: "is bamboo actually sustainable, or is that just what every brand says?" It's a fair question, and it deserves a real answer instead of a hangtag adjective. So here's the long version.
Step one is the plant, and this part is the good news.
Bamboo grows fast — most harvestable in three to five years — and it does it on rainfall alone. No irrigation. Compare that to cotton: a single cotton t-shirt's worth of fibre can take around 2,700 litres of water to produce, and growing enough cotton for a garment typically requires steady irrigation in a way bamboo simply doesn't. Bamboo can grow without pesticides, regenerates from its own root system without replanting, and, as a fast-growing grass, pulls a meaningful amount of carbon out of the air while it's doing it. If you stopped the story here, bamboo would look almost too good to be true.
Step two is turning that plant into fabric.
Raw bamboo is a woody grass. It doesn't turn into something soft enough to wear against your skin without a real industrial process in between. The most common method, the one behind the vast majority of "bamboo" clothing and bedding sold today, is called the viscose process. Bamboo pulp gets dissolved using sodium hydroxide, carbon disulfide, and sulfuric acid, and turned into a fibre that can be spun and knit. In most facilities worldwide, only about half of those chemicals get recovered and reused; the rest is a cost of doing it the cheap, common way.
This is exactly why we can't just call a garment "bamboo" on its own. Regulators on both sides of the border have been explicit about this for over a decade: fabric made this way has to be labelled "rayon made from bamboo" or "viscose made from bamboo," because the plant and the finished fibre are, chemically, two different things with two different footprints. This isn't a technicality. In 2022, the FTC fined Walmart and Kohl's a combined $5.5 million for marketing rayon products as "bamboo" without qualification. It was the largest civil penalty in FTC history for this kind of claim, on top of earlier settlements against Amazon, Sears, Macy's, Nordstrom, and Bed Bath & Beyond going back to 2013. The word "bamboo" by itself, on a fabric label, is a legal red flag.
We're not going to pretend we've solved this. What we can tell you honestly is what we actually control: how the fabric gets finished once it reaches our manufacturing partners, and how carefully it gets checked before it ships. It has more to do with how the fabric is handled after processing than with bamboo as a fibre in the abstract. It's also part of why we've been comfortable backing every pair with a two-year warranty. It's not a marketing number, it's just what happens when someone is actually checking the product before it goes out the door.
We're telling you all of this because we'd rather you trust the specific, checkable version of our story than the soft, feel-good one. "Sustainable" and "eco-friendly" are words getting harder to trust for good reason - Europe's new Green Claims rules are cracking down on exactly this kind of vague language starting this fall, and honestly, that's overdue. We'd rather say: bamboo grows well, most bamboo fabric is processed in a way that has real trade-offs, a cleaner process exists but isn't yet the norm, and here's exactly what we do with the part of that chain we control. For example, we purchase OEKO-TEX 100 certified fabric, so we know that it's safe for sensitive skin, and has been actually tested to prove it.
If that's more nuance than you expected from an underwear brand, that's kind of the point. Ask us anything about it - we'll give you the real answer, not the shorter, better-sounding one.
-Sarah+Rob
Sources: FTC — Bamboo Textiles guidance | ASI — FTC fines Walmart, Kohl's for bogus bamboo marketing | Better Cotton Initiative (nonprofit) — Cotton's water footprint: how one t-shirt makes a huge impact | Unsustainable Magazine (independent editorial) — Sustainability of bamboo, 2026 facts vs. greenwashing