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Weight Loss

Put Your Body Into Fat-Burning Mode

Weight-loss expert and bestselling author of FAST BURN!, Ian K. Smith, MD, provides a step by step guide to speedy and sustained fat loss.

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“I am always in search of creating programs that are not only topical as far as what the latest science and research is showing but also are the most user-friendly,” says Ian K. Smith, MD, author of the SHRED series, The Clean 20, and his latest, Fast Burn!: The Power of Negative Energy Balance. “So I really wanted to continue the conversation about ways to eat cleaner foods—which continues to be a very strong and important movement, and I’m happy about that—but I also want to talk about how we can use intermittent fasting not necessarily in a rigid way, but in a way that’s more customizable. Fast Burn is a way to take both of those concepts—clean eating and intermittent fasting—to the next level while also being extremely accessible to a broad array of people.”

The nine-week program is broken into three parts—Ignition, Intermission, and Acceleration—that include detailed meal and snack plans as well as two “jigsaw weeks” (one plant-based) that encourage readers to structure their own “clean fasting” journeys. Plus, it offers 33 delicious, simple-to-make recipes designed to delight intermittent fasting vets and newbies alike. The program’s signature Burner Smoothie alone features apple juice, apple cider vinegar, coconut oil, blueberries, apples, bananas, spinach, lemon juice, and ice. “It’s really delicious and filling,” the good doctor adds.

Q&A with Dr. Ian K. Smith

BN: What is negative energy balance and how, in essence, do we achieve it?

IS: Energy balance is the foundation of weight gain and weight loss. Food calories, drink calories—that’s energy. Our body requires a certain amount of energy just to live, just to exist. And it requires more energy depending on how active we are and what we’re doing in our day-to-day lives. The idea is that in order to lose weight, you have to put yourself in a negative energy state, which means that your body’s demand for energy exceeds its supply. That’s negative energy balance. If you consistently put yourself into a negative energy balance state, you’re eventually going to lose weight because your body is no longer in an energy surplus and you’re burning off more calories than you’re actually consuming. Those calories can come from energy stores, particularly fat.

BN: How does this book break down intermittent fasting for newcomers while taking this way of eating to the next level?

IS: What I try to do in the book is explain the basic, most popular types of intermittent fasting (IF) and then incorporate different types into the program. There’s the 5-2 method, the time-restricted feeding method (TRF), and the alternate day fasting method. Rather than have users follow just one strategy, I mix it up, because I think certain people are more compliant or can do better with a certain style of intermittent fasting—and far be it from me to say you can only do TRF. Maybe TRF is the best way to lose weight according to research, but if you can’t follow it then it’s not going to be a success for you. So I give people the option to try different types of fasting methods and find the one they like the most. Once they finish their nine weeks, they may decide to follow a particular strategy of IF as they go forward.

BN: Which foods and drinks are no-nos on this program?

IS: A no-no always for me is soda, an absolute waste of calories with zero nutritional value. I’m not asking you to have a sugar-free diet. I’m saying let’s be mindful of where we’re getting the sugar from and how much of the sugar we’re getting. So I’m okay with freshly squeezed lemonade, which is lemon, water, and some sugar, versus soda, which is sugar and everything else that’s processed and synthetic. And I try to encourage people to eat snacks that have fiber and/or protein because it’s a better strategy. They’re able to feel full longer when they do that. That’s very important to me. However, I don’t say you can’t have a chocolate chip cookie or a brownie.

BN: Which types of versatile foods should we stock to start this program?

IS: Legumes such as lentils, peas, and chickpeas are very important to a transitioning program because they’re extremely versatile foods—you can cook them in so many different ways—and they fill you up nicely. I also think people should try alternative types of pasta like chickpea pasta and whole-wheat pasta, which are not only healthier than conventional pasta, but are really tasty.

BN: What is a jigsaw week in your program—and why have it?

IS: Instead giving you a very specific daily meal plan of things that you can eat or must eat—like I do in the other parts of the book—I provide options during a jigsaw week. I lay out a long list of breakfasts, lunches, and dinners, and I want you to piece together what your daily meal plan is going to be like. One of the big purposes of this book is to get people to make better, healthier, smarter decisions on their own. A jigsaw week is an experimentation—you get to test yourself as to how much you’re learning about making smarter decisions.

BN: Describe the significance of the Daily Double—meaning a second daily snack—on a 5-2 IF schedule during the program’s final two weeks.

IS: The 5-2 schedule may be very tough for some people because it’s five days of “normal calorie” eating and two days of severely restricted calories, relatively speaking. And on those restricted calorie days, people may find it really tough to stay at 800 calories or less. So if someone is really having a hard time, then I make that extra snack available to them. You’re not going to really do any damage by having an extra snack. You would do damage by having a whole other meal, another 400 or 500 calories. But a snack prevents people from falling off the plan and reaching for things they shouldn’t be reaching for.

BN: In terms of maximum fat burning, how does exercise factor into Fast Burn?

IS: Exercise is one of the most efficient and effective ways to put our bodies in a state of negative energy balance. Because exercise automatically and immediately increases our energy needs. So if we do really good exercise, we’re going to increase our energy needs right away, and then we are in control of how much energy we consume. Then we can actually keep our energy consumption down while increasing our energy demand, and therefore expanding or elongating or increasing that negative energy balance.

Dr. Ian K. Smith’s Favorite Recipes From Fast Burn

Pancakes: I love pancakes, so I put my grandmother’s pancake recipe in there. People typically can’t have pancakes on a weight-loss program, but I think life without eating pancakes is kind of a half experience.

Beef Burrito Bowl: I love this recipe! A lot of people might be surprised that you can have something like this on my program. I think you can have red meat in moderation.

Red Pepper and Scallion Scramble: This recipe is very flavorful—we’re not compromising on taste.

Baked Apple Heaven: This recipe is all about creating things that are easy to make. So you have apple, rolled oats, pecans, nutmeg, cinnamon, and coconut oil. And a little cider and maple syrup. You core the apples and pour all these ingredients in there. It’s so savory and sweet at the same time. I love how easy it is, and having lots of whole grains and vitamins in the apple, it really answers the call in the morning.

Make It! Baked Apple Heaven