Glass is the eco-friendly lunch box winner. Heavy, but worth it.

Glass is the most eco-friendly lunch box material after stainless steel, but it comes with a tradeoff you need to know.

Sure, glass is heavier and breakable. But it’s made from sand, lasts basically forever, doesn’t leach anything into your food, and is infinitely recyclable. A glass container you buy today can still be in use in 30 years, and when it finally breaks, it goes back to being glass. That’s about as green as it gets.

Silicone is the practical runner-up. It’s lightweight, non-toxic, and flexible, so it’s popular for snacks and bento-style dividers. The catch: silicone is very hard to recycle curbside. You usually have to mail it to a specialty recycler, and many people just throw it out. Still, if you need something unbreakable for a kid’s lunch, silicone beats plastic every time.

Bamboo looks eco-friendly, but watch the fine print. A lot of bamboo lunch boxes are bamboo fibers mixed with plastic resin to make them durable, and that blend is essentially non-recyclable. Truly solid bamboo containers are fine, but they’re rare and often coated. If you go bamboo, check what’s actually in it.

If you can handle the weight, a glass container with a silicone sleeve is the last lunch box you’ll ever buy.