Instruct: Classify Amazon reviews into positive or negative sentiment
Query: It works

I got this because I have a white spot on my fingernail. That is supposed to be a sign of zinc deficiency, but I didn't want to start taking it if I didn't need it. Guess what? I don't. After one second of having this in my mouth, I quickly realized that. It tastes pretty awful! It's a really effective, inexpensive way to keep yourself from taking what you don't need or letting you know when you've had enough. Great buy!