Steel and glass beat plastic every time

Stainless steel and glass are the safest lunch box materials if you’re trying to avoid BPA and phthalates. If you’re buying new, skip plastic entirely.

The problem with plastic isn’t just BPA. “BPA-free” plastic often swaps in BPS or BPF, which aren’t proven any safer. And phthalates are still used in some plastic food containers and lids to make them flexible. All of them can leach into food, especially when the container is heated or holds acidic food like tomatoes.

So your best bets:

• Stainless steel — no lining, no plastic mouth contact, nearly indestructible. Just check the lid. If the lid has a plastic seal, keep food from touching it, or grab a brand with a silicone gasket.
• Glass — totally inert, zero leach risk. Heavier and breakable, but safest possible where food touches the container.
• Food-grade silicone — generally considered safe and is what most experts recommend if you want a flexible, non-plastic option. It’s not perfect, but it’s a big step up from plastic.
• Polypropylene (#5 plastic) — if you must use plastic, this is the least-worst option. It’s the most stable common plastic and used in most “safe” lunch boxes, but it’s still plastic. Don’t microwave it, don’t run it through a hot dishwasher on the bottom rack.

Leather, canvas, and insulated fabric lunch bags are fine for the outer layer since they don’t touch the food directly. The only thing that matters is what’s in contact with your meal.

These are not where you save five bucks. Your lunch sits in that container for hours, and heat, time, and acidic food all make leaching worse.