I've been taking Metformin(glucophage xr now) for almost a year. It makes your cells more sensitive to insulin. As far as aiding in weightloss itself, i am not certain but if you are taking enough that your cells begin to become more insulin sensitive then you will produce a bit less insulin and that can lead to less fat storage. How much, i don't know. i did not weigh on it until after i had begun to also control my carbohydrates in July. i still craved carbs while on it but not low-carbing but i ate fewer of them and also i had more stomach upset if i overdid the carbs then.
I am on 2000mg of glucophage xr, which is the maximum dosage for the extended release. i was put on that because the regular Metformin/glucophage was too hard on my stomach. i take my four horse pills in the morning .. smiles.