Piling on the fat is about as effective as smoking if you want a reliably slow way to shorten your lifespan by a decade or more [1] while at the same time considerably increasing your lifetime medical expenditures [2].
That visceral fat around your organs works a number on your biochemistry, increasing chronic inflammation [3] with all its detrimental consequences. That is bad enough but other unfortunate and more poorly understood changes take place in metabolism when you eat a very high calorie diet consistently, of the sort needed to sustain a lot of fat tissue, pushing nutrient sensing mechanisms into overload. [4]
There is magical thinking everywhere when laypeople talk about medical technologies. But this fat-related example is particularly egregious.
[1]: http://www.eurekalert.org/pub_releases/2010-07/iaft-sfl07121...
[2]: http://www.eurekalert.org/pub_releases/2013-12/dumc-hcc12161...
[3]: http://www.houstonmethodist.org/body.cfm?id=495&action=detai...