dieting is hard enough, i'd attempt that first. once you can lose a lb a week, then i'd try to incorporate fasting. being overweight has it's own health risks as we age and being fit enough to vigorously exercise might have just as much benefit as fasting, might even duplicate some benefits.
and one major reason to stay fit is to be healthy enough to qualify for a clinical trial that might reverse pd. gotta be ready just in case.