Hi!
You can definitely do Insanity, but you should also eat healthfully while you are doing the program. You need enough fuel to do the program well and lose weight. I have added you as a buddy. If you want, I will send you your recommended calories per day. You should set up a free account on myfitnesspal.com. Once you have done that, we can set in your calories and recommended nutrients.
If you stick with the program and eat well, you will see wonderful results in your body. I know that losing weight is your main goal, but with Insanity you will not only lose weight, but also firm up and tone and develop nice muscles. During the first few weeks of Insanity, you might not lose, and might even go up just a bit as your muscles build up some acid. But that will come off after a few weeks, and you will find that you are trimmer and leaner.
Insanity is a great program! I am just now about to push play

Beth
Elite Home Fitness Group