Hiya there. The rash
you described appears to be a 'nummular eczema' or 'asteatotic eczema'. You will most likely benefit from the use of emollients applied on wettened skin surface. For starters though, a mild corticosteroid cream may help decrease the eczematous cycle if used for a short period of 48-62 hrs. Please do avoid soaps & use cleansing bars eg. Dove that are readily available in any supermarket. Weight loss
& diet control will not have any direct bearing but will surely help your quality of life in the long run. Wish you well..cheers!