Instruct: Classify the given Amazon review into positive or negative sentiment.
Query: Works great but not without side effects

It is the first time i am using this product. It works great and does what it is supposed to. Also, when taking it, I have developed aversion to certain junk foods and soda is absolutely off limits. I suppose it is a positive effect you need to cleanse your body, but in addition i got stomach cramps that interfere with my daily life.