2lbs a week is a good way to go. 21 weeks, right? DO IT! Post your progress here....
2 lbs per week may be unrealistic.
Again my New Years Resolution is to lose weight
If I can do a lb a week I will be most happy.
Usually the first week or two 5 or more lbs comes off each week and then it gets very hard.
I don't know if it is true but I heard that changing to a healthy diet eliminates a lot of sodium from the system that is causing water retention and that water loss from change in sodium balance is the reason for the initial loss of many pounds.
Math
Person eats 2000 calories a day. (OP possibly 2500)
One must burn 3600 calories to lose one lb of fat.
500 calories x 7 days in 1 week = 3500 lb in one week.
Average person would have to cut calorie intake in half to lose 2 lb a week.
I think cutting calories back 12-15% is where the metabolic rate slowdown occurs.
Walking at about 3 mph (walking a dog pace) would burn about 350 calories for the OP in 1 hour.
So if he could cut back on calorie intake about 12% (300 calories)
Walk 1 hour (350 calories) that would be 4,900 calories a week (over a pound) keeping his metabolic rate up and less likely to go off the diet because he is not eating so much less than he is used to
It would take 30 weeks to lose 40 lbs