hello everyone!
I have a question about calorie intake. I have like 200+ pounds to lose and I am trying to get a straight answer on how many calories I can eat and still lose weight. According to fitday.com I need like 4300 to just maintain my current weight and I have been eating like 2500 -3000 calories a day and weighed myself this week and gained 3 pounds. Also I have been lifting weights and walking. What is it I am doing wrong? Could I be retaining water or something? Take in even less calories? If I go under 2000 calories I am hungry all the time it seems. I am getting extremly frustrated with this. I am determined not to give up but if I don't lose anything I can see myself getting frustrated and giving up. Any advice would be great!
Dani

Also, did you add sleep as an activity? That will decrease your calories a bit, and it's something a lot of people forget to add. Some say Fitday automatically includes sleep, but how does it know if I sleep 3 hours or 12 hours tonight?
In any case, I think it's BMR calculations are too high for many many people, so adding sleep helps to lower it some.
Some of them want you to fail! If you've only been doing this for a week, give it more time! Scale fluctuations can be caused by so many things -- water, tom, sodium... 

Thank you EVERYONE for all of the information you have listed on this thread. I too use an online calorie tracker, and all of this information is so interesting. When I started my plan two weeks ago, I had 107 pounds to lose when I weighed in. The tracker has had me eat every day between 1230-1560 calories, and that is up a little because of the 30 minutes six days a week of exercise I do. I have lost 9 pounds now, and I haven't felt hungry, so I'm hoping this range is correct for me. I have, for most days, been eating in the upper range of my calories. Thank you again for all the info!