Correct me if I'm wrong, but I think that rapid weight loss induces a huge NEFA release from the adipose tissue. These NEFA are cleared partly by the liver where there are transformed into TG and thus increase hepatic steatosis. On the other hand, bariatric surgery is known to improve T2D and insulin resistance very quickly and before significant weight loss. As high glucose and insulin levels stimulates hepatic de novo lipogenesis, TD2 and IR improvement decreases hepatic lipogenesis and thus steatosis. I guess that in the case of bariatric surgery the balance between decreased lipogenesis and increased NEFA uptake is in favor of a reduction of steatosis.

Thank you for you response! So one could perhaps assume that the hepatic steatosis seen after rapid weight loss is only a temporary reaction that will not progress to NASH, and that this steatosis will resolve once the beneficial effects of weight loss ensue, such as improvement in IR ??

I agree, I myself have observed some cases in my own practice, with a good prognosis, but obviously I do not recommend in any case dietary regimens that achieve rapid weight loss!