Why do some people get wider when they gain weight but others just get a bigger belly? different foods and lifestyle? or just genetics?

Combination, genes: are basic instructions; the controlling issues are which ones are read/expressed in what combinations; 1 of the main reasons cell behaviors vary so widely, e.g. cornea to neurons to bone cells with largely the same 30K gene set within. Thus a big issue is how we use/influence the genes we have: (a) how we use our body, (2) what we put into our body, (3) how much we put in (4) what ratios, etc.