Decreased Caloric intake = Increased metabolism body of fats??

So, this something I haven't seen addressed here yet. Perhaps my keyword searches through past threads were off.

Any sort of info out there on limiting Caloric (food) intake in hopes of having your body metabolize fat (presuming one has weight to lose) to in essence rid body THC metabolites faster? It makes sense logically to me seeing as how exercise is recommended prior to UA tests.

Also, since we are on the topic. Could not eating on the day of or day before increase the amount of THC excreted in an individuals Urine? (assuming here that the body would be breaking down fat stores for energy increasing measurable level)

I suppose all my questions regard metabolism. Can anyone shed any light here?

I understand this would be an unhealthy approach to any situation but I am curious none-the-less. Strenuous dieting a couple weeks before test to possibly increase passing likelihood.