1+ to getting an MD and/or Nutritionist involved if you can.
Every body is different... but you will undoubtedly hit a "plateau" at some point - as I think we all do.
There are ways to optimize
weight loss, and ways to optimize
fat loss. And not all bodies respond the same.
Definitely focus on "lifestyle change" - and that doesn't necessarily mean grave deprivation. The more you adopt healthier habits incrementally, the easier I think it is to maintain those healthy habits.
I know
gradually can sound boring, non-competitive, uninspiring and downright impossible if you don't see big results immediately - this is one of my greatest challenges. But it really is best overall for your health, fitness, emotional well-being and sustainability.
For me (and many), losing the weight isn't so hard - it's keeping it off. I finally had to spend some time trusting that I could
maintain my weight over a period of time before I could start losing weight again,
gradually. Otherwise I "yo-yo" the same 25lbs - lost then gained - over and over again.
It's great to have goals... As I get older I value my health and fitness measurements and abilities (ie; keeping blood pressure low, the ability to get in a quick km in the pool before work, etc.) more than I value what I actually weigh in pounds.
Good luck and please share with us your learnings and success!