I agree with Dan. (I pretty much always agree with Dan.

)
50 pounds in 25 weeks is an extremely aggressive goal. It is *possible*, but unless you're on a well-defined plan and working with health or nutritional professionals, it's not likely that you'll be able to both achieve the goal and stay healthy.
Before setting a really strict goal like this, ask yourself: How will you feel if you lose 25 pounds in 25 weeks? That's half of your weight goal... Would you feel like a failure for missing your target date? (I certainly hope not- you'd be 25 pound healthier!)
When you embark on a healthy eating plan like this, you'll probably have weeks with big losses, and weeks with no losses (or even little gains). The goal is to get healthy and fit- you're not in a race with the calendar!
That said, it is nice to set goals and to feel the satisfaction of meeting them. Small goals work best for me- I just watch for that next 5 pound mark.
I don't really set big goals with timelines. I DO chart my weight loss progress and then project where I can be in the future- more of a "It's *possible* for me to lose X pounds by X date." I find that I don't set myself up to feel like I failed if I miss the date. Instead, this is something I can use to motivate myself when a Krispy Kreme doughnut is tempting me... "I can choose to eat this doughnut, *or* I can try to lose that next 5 pounds." Does that make sense?
No matter how you choose to set your goals, or what eating plan you embark on, the MOST important thing is that you are getting healthier. Whether you lose 50 pounds by August or 25 pounds by December, YOU WIN, because you've improved your health!!
Kathy's motto: You don't need to be perfect, you just need to be better.
