Instruct: Classify a review into positive or negative sentiment.
Query: Great natural sweetener!

I have been using SweetNlow for a long time because it doesn't have any calories and is extremely sweet. But after taking a course in Chemistry, I decided to switch to natural stuff. Sugar has the same amount of calories per teaspoon as fructose, but is not as sweet, so you need a lot of sugar to make the coffee sweet. One teaspoon of fructose is enough for me and has only 15 calories.