Welcome! This is a great diet, but you do have to follow its tenets assiduously in the first few cycles to get the best results.

The good news is: you get GREAT results.

The bad news is: you have to modify your eating habits. But then, all diets require that, so maybe the news isn't so bad. At least with the 17DD, you have a complete food list for each cycle and a pretty simple plan.

Yes, exercise is required. If you are currently sedentary, a simple walk for 20 minutes a day will do in the beginning. But be prepared to increase that as you proceed through the cycles.

Your results can be spectacular, though they do depend on how closely you follow the food lists, how much and how well you exercise, and -- sigh -- how old you are. I'm 50-ish and I have to work out a lot to get results from anything, and the minute after I slack off, I start to gain back.

The most difficult part of the 17DD is the first Cycle. The food list is restrictive and you are not allowed starches (as opposed to carbs -- carbs from fruits, dairy, and veggies are permitted). Many people who love starchy foods have difficulty adjusting to the first cycle, but I promise if you do, your cravings for junk will go away in about a week.

Many of us have struggled with getting enough calories in the first Cycle as well. Especially if you keep track of your sodium intake on MFP. In the first cycle, you are allowed unlimited lean protein (from the list) and unlimited vegetables (see the list in the book). You are also allowed two servings of a probiotic dairy (yogurt, kefir, etc.) and two servings of fruits (see the list -- must be eaten prior to 2pm each day).

Most of us have had to repeat Cycle 1 after the first shot. It takes tracking and work to find the right balance, but it is definitely worth it.

Good luck!