Everyone's fat metablolism is unique. What is important is that you learn how yours works.
What worked for me was to lose 40 lbs on the South Beach diet, before starting transition. SBeach is healthier no-sugar/no-fast-carbs/low-fat diet.
What was important about this, is men do lose weight easier than women, so getting down to my proper weight first seemed like a good strategy. But more important, this proved to me that I wanted badly enough to transition, and that I had the self-discipline to transition.
It took nearly a year, and I didn't lose weight every single day, or even every week. I backslid a couple times. But when I hit rough spots in my transition, I remind myself about tha diet, and gives me the confidence to get through it. Not just the diet, but other things like the diet too.