Unintentional weight loss can occur because of an inadequately nutritious diet relative to a person's energy needs . Poor nutrient utilization can lead to weight loss, and can be caused by fistulae in the gastrointestinal tract, diarrhea, drug-nutrient interaction, enzyme depletion and muscle atrophy.It is relatively safe to use and provides substantial results in terms of controlling blood sugars. When it comes to metformin and weight loss however, the results are simply not supportive of its use solely for this reason. Some studies however have reported metformin weight loss–in some cases up to 2.9kg.