The Metabolism Miracle: 3 Easy Steps to Regain Control of Your Weight . . . Permanently is another book repackaging old information and bad statistics as a "miracle." I automatically have a bias against any book selling a "miracle" because the author doesn't know how miracle is really defined.
I'll start with some advice, instead of buying this book just jump to Phase 3: Find an online calculator to help you figure out your macronutrient balance with 30-35% of your calories coming from carbs. Work out 30 minutes a day, including regular weight training, and see what happens...for my reasoning, see the below.
First, like most self-help books the author always writes to "YOU." She also preys on the insecurity that many people feel "My friend works out less than I do but stays skinny..."
She presents a long list of "symptoms" (like "stress...fatigue...fat roll around the middle") that every human being suffers from and if you identify with it then it must mean that you have "Metabolism B," a term that the author makes up. Even the most physically fit die-hard fitness buffs I know struggle with their cravings, it's part of the human experience-- particularly for women who have other harmonal imbalances to consider.
But Kress uses bogus reinforcers like "Your strong reaction to this list of foods is just one more affirmation that you have Metabolism B." She makes up bogus statistics like "more than 45 percent of people struggling to lose weight are born with genetic predisposition to Metabolism B." This is a completely unverifiable (therefore, false) claim. She is selling the message that you were born differently therefore this "Miracle" is the only thing that will work for you. That's not science, it's dishonest salesmanship. While she claims "modern" research supports her, she conveniently provides no references.
So, the process is three-fold: 8 weeks of nothing more than 5 net carbs in a 5 hour period. Another period where you can have a bit more. And the last period, where 30-35% of your calories can be carbs. Meanwhile, you're supposed to be exercising 30 minutes a day and focusing on muscle/strength training (which IS medically recommended-- you don't need her book to tell you these things). I don't see how this is much different than Atkins or South Beach with three phases that include progressively more net carbs.
In Phase 3, Kress simply repackages the TDEE-based calorie and macronutrient calculators that you can find on hundreds of websites, these take into consideration your age current weight (she provides her own chart for this). She is not the only dietician who says "everyone is different," and she tears down straw men repeatedly to sell her "Miracle." One problem is that she also hints that the other 65-70% of your calories be low on fat (and therefore high-protein) without helping you figure that out (I assume because that's been covered in plenty of other non-"Miracle" diet plans.) And it requires looking at ingredient labels and counting calories, something she wants to make you think you don't have to do in the first few pages of the book. Phase 3 logically requires that you do it.
Not all exercise programs are equally efficient in burning calories, chances are that if you bought this book you're not working out 30 minutes a day or are simply using a treadmill/elliptical or only focusing on cardio workouts. Kress is right to point out (toward the end) that building muscle shreds fat and boosts metabolism. Part of the reason weight gain becomes more of a problem after age 30 is because your muscles begin deteriorating unless you're working harder to build them up (it's called sarcopenia, and has nothing to do with "Metabolism B"). This is why people are more likely to fall into her Metabolism B "symptoms" as they get older. High-intensity interval training will boost your metabolism more than 30 minutes on an elliptical and actually make an impact on your DNA, that actually is supported strongly by scientific evidence. And if you're working out regularly, then the International Society of Sports Nutrition recommends a diet consisting of 40-60% carbs (read the linked report for reasons). Nothing "miraculous" about it, this is old news.
I have problems finding anyone publicly online who has completed all three phases, kept the weight off, and feel good about their lives. The author cautions those who want to stay on Phase I or II that this is "dangerous" and "not healthy." Ketogenic diets (what Phase I is) should only be used by a select group of people and has a wide range of potentially harmful side-effects. The author addresses the source of the fears of people who mistakenly stay in Phase I-- they've been burned by going off of other low-carb diets and experiencing weight gain. This book isn't going to help you with your fears or help you achieve your health goals without exercising.(The author has apparently reversed her decision about staying on Phase I).
The promise by Kress that your body will be "permanently reprogrammed" is also false, as she recommends spending time repeatedly "reprogramming" your body if you mess up. In the end, you'll be getting 30-35% of your calories (requiring counting) from your diet and working out (with weight training) 30 minutes/day. Why not just start doing that now?