Well ... my weight was sustainable to a point, because couple of months after I quit the diet I got pregnant. So it went up a bit after my pregnancy cravings. After that, It was okay until about a year ago when I went on blood pressure meds and it started creeping back up because they lower the heartrate/metabolism. I spoke to a couple of people who had done Atkins when I was 'on the diet.' They had kept it off for a couple of years. But I think it only works for good if you treat it as al ifestyle change and not a diet. As with any diet.
By the way, the first two weeks are a bit more restrictive. It's called the 'induction phase' and those 20 carbs aren't supposed to come from just anywhere. An ounce of cheese is 1gm. And if she eats processed meat, things like hot dogs are going to ring in at about 5gm each. Creamer for your coffee can be 1gm - 5gm unflavored, depending on what kind you use.
Once she's past the induction phase, she can even slice up
part of a banana or such with her breakfast. I think a banana from my fingertips to my wrist is between 15-20. And a cup of milk is between 9-12 (depending on fat content) so you can still get in your calcium besides cheese. And nothing wrong with eating 1/2 slice of whole grain toast (7-11 carbs for 1/2 slice) instead of two whole pieces that a restaurant gives you when you want some with breakfast.
Just remember you don't want all your daily carbs at once. You want to avoid an insulin spike. I have a digital scale that helps me count when I'm not sure, and it comes in handy. Several years after Atkins, one of our girls was diagnosed with diabetes, so I still have to count those puppies and pay attention to fast sugars and such.
One of my best friends is now
CalorieKing - Diet and weight loss. Calorie Counter and more You can get all kinds of nutrition information (carbs/sugars/calories/cholesterol/etc) on everything from fresh produce to fast food items. Give it a peek.