Fat is associated with health problems, but it may not be the cause of those problems. Fat may be a defense mechanism against unhealthy eating:
If merely the amount of excess fat is the direct cause of metabolic dysregulation then removing that fat through surgery should obviously result in metabolic improvement. Unfortunately, this is not the case. In fact, an excellent prior study has shown that liposuction does not make obese individuals healthy.
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Obese individuals with metabolic problems who are prescribed a class of drugs called thiazolidinediones or TZDs for short, actually grow more fat cells, get fatter, but also get healthier.
Currently, the emerging theory of why obesity is associated with metabolic disease risk suggests that it is not the excess amount of fat that results in problems – but rather, it is the inability of the fat tissue (specifically subcutaneous) to expand enough via the development of numerous, healthy adipocytes or fat cells to store all the excess calories being ingested (more details on that here).