In my nightmares, I'm eating an energy bar. I unwrap it, scarf the whole thing down, and then come to the instant, heart-stopping realization that I have just poisoned myself. I thought for sure I checked the label—I always check the label—but it doesn't matter now because I've already swallowed. The gluten is already in my system.

This is when I wake up.

I know that it sounds melodramatic, even paranoid. I also know that if you experienced blinding pain, a gastrointestinal meltdown, and lasting internal damage every time even a smidge of gluten passed through your lips you'd be paranoid too. You'd pepper your waiter with questions about what exactly is in that sauce and hesitate to trust his casual "I think it's fine" response. And if you had a way to check whether that waiter actually knew what he was talking about, you'd probably take it. If only for the vindication.

For years, I hoped for a device like that because I have celiac disease. My body overreacts to gluten and starts attacking my intestinal lining instead, so I can't eat anything that's made from the three gluten-containing grains: wheat, barley, and rye.

I have weirded out countless waiters with questions and sheepishly asked if they could please remake that salad because they put bread in the bowl when I asked them not to and now I can't eat my $13 lunch. And for what felt like a lifetime, I had heard that some mystery company was developing a sensor that could help me feel confident in my food. The online celiac communities buzzed every time an article came out claiming a gluten sensor was in the works. My fellow-celiac cousin and I would mention it passingly when we were out to eat together, never truly believing we would ever be able to buy such a device.

And then, last week, I got it. The Nima. The thing I had been awaiting since my diagnosis nearly four years ago. And it wasn't what I expected.