It cannot bounce back. The elastin is replaced by collagen over time. It happens in everybody as they get older anyway but for fats it is accellerated because of endocrine changes. That's one of the lies about "HAES". They bang on about the secondary problems such as heart disease and strokes. But fat in the body makes it change Endocrine Changes in Obesity - https://www.ncbi.nlm.nih.gov/books/NBK279053/  Obesity is the consequence of a positive energy balance, which can result from an increased energy intake and/or decreased energy expenditure. It may be described as a failure of the body's homeostatic mechanisms to match energy intake with expenditure. Adipose tissue is involved in the metabolism of cortisol since the enzyme 11 Beta-hydroxysteroid dehydrogenase-1, which converts cortisone to cortisol, is highly expressed in adipose tissue. The cortisol response to a variety of stimuli such as ACTH, CRH, or meal ingestion is altered in obesity.  Effects (form wikipedia - https://en.wikipedia.org/wiki/Cortisone))  Oral use of cortisone [I'm presuming endocrine effects are similar] has a number of potential systemic side-effects: hyperglycemia, insulin resistance, diabetes mellitus, osteoporosis, anxiety, depression, amenorrhoea, cataracts, Cushing's syndrome and glaucoma, among other problems.  see also https://en.wikipedia.org/wiki/Cortisol https://www.ncbi.nlm.nih.gov/pubmed/3062759