Please do be aware that metformin helps lower blood sugar. If you are already on the low end of normal, this is especially important to know because you could end up in a hypoglycemia condition. Especially if you skip meals or exercise too rigorously. The way metformin works is that it reduces glucose absorption and then of course also helps the body be more sensitive to use insulin to move glucose from the bloodstream into individual cells. The drug may reduce your appetite (as a result of side effects like diarrhea and GI discomfort), but the way it works to help most of the people it is prescribed that want to pair it with other drugs to maintain or work towards a healthy weight is by helping to address the blood sugar/insulin sensitivity. I'm not sure why you would go on it if you already have your blood sugar in a state that appears to be healthy, but I am sure your doctor must have some sort of reasoning and will help you monitor what is happening. Good luck!