There are no specific numerical criteria. Generally, MWL refers to a state where significant weight loss occurs from a state of severe obesity, resulting in excess skin and tissue sagging, and impacting daily life. It is not just the amount of weight lost that matters, but whether there are physical and lifestyle impacts.
When skin is stretched for a long period, its ability to return to its original state weakens. The longer the period of severe obesity, the more skin elasticity decreases. Therefore, even after fat is reduced, excess skin and subcutaneous tissue may remain.
It's not just a cosmetic issue. Excess skin caused by MWL can lead to symptoms such as the following and is a condition that should be considered from a medical perspective.