No you don't have to do it for the rest of your life, but I would do it while dieting. From what I read, a high Carb meal (a refeed, NOT CHEAT meal), with low or no fat and lean protein will also effect leptin levels/ receptors positively as well.
I have been doing this in the morning fasted,(only unsweetened green tea & 1 cup of black coffee beforehand)then walking for 45-60 min, I do not do it every day, but usually 4/5 days a week. I am doing Nate Miyaki's Paleo hybrid diet, I have had good results so far, I skipped my refeed last week to see is it increases my fat loss, or if there is no real difference, or if I stall. I work nights and am older, I am really happy with the results so far.