you should be proud of even asking and putting ourself "out there" ... there is so much advice I could (and will) give you if you want it... i just really wanted to get on here and say "Way To Go" for having a goal, asking the questions and committing yourself to your goal.
40 lbs is a bit less than 1lbs per week... that might be an easier way to look at it... and, from everything i have read, that is a reasonable amount to loose a week, 1lbs or so...
what are your health issues? do you binge? are you able to workout (ie any physical issues)...
remember, we ladies are not doctors, or personal trainers, or dieticians... so it is only my experiences that i can share
... and i have tons of it!!!