But now he's added a bunch fat cells he's stuck with the rest of his life.
what does this mean? what are the implications?
Well, at the cellular level there are two ways to get bigger. Either your cells become larger or they divide and grow in number so you have more cells.
This poster is implying that Zach's body responded to his caloric excess by growing new adipocytes (fat cells). The poster is further implying that now that Zach has millions more adipocytes than he did before, his body will more efficiently store fat, which will make it much harder for him to lose weight or keep of weight if he does lose it.
As far as whether this is true or not I do not know enough about adipocyte biology to comment. If you were really interested you could go on pubmed (
www.pubmed.com) and look up some articles in peer-reviewed academic journals to see what the concensus of the scientific community is on this subject.
However, keep in mind the human body (or any biological system) is extremely complex and despite the advanced state of science we have today, there is still a lot that is unknown, and there is a lot that is believed to be true today that will probably be proven false in the years to come.