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The Fast Beach Diet

The Super-Fast Plan to Lose Weight and Get In Shape in Just Six Weeks

Foreword by Dr Michael Mosley

About The Book

With a foreword by Dr. Michael Mosley, this is FastDiet 2.0, a complete diet and exercise plan designed to help you get your ideal beach body in just six weeks!

In the #1 New York Times bestseller The FastDiet, Michael Mosley shared his groundbreaking 5:2 plan—eating normally five days a week, fasting for two, and becoming slimmer and healthier as a result. Now, with The FastBeach Diet, a modified, high-intensity version of this plan, Mimi Spencer will help you get beach-fit in no time!

This six-week weight loss plan gives you powerful, proven tricks and tips, including:
· Plateau-busting techniques to make the 5:2 plan work for you
· Mindfulness methods to help you be a conscious eater
· Habit-changing techniques for non-Fast days
· A high-intensity training method that can be done in less than ten minutes a day
· Dozens of all-new, calorie-counted summer recipes

With a full-color, week-by-week planner to keep you on track, this speedy diet plan won’t let you down. Watch the pounds fly off as this no-fuss exercise and diet program gets you ready to hit the beach—the Fast way.


The FastBeach Diet Chapter 1 The FastDiet Revisited . . . and an Invitation to the Beach
“A year from now, you will wish you started today.”

There are many good reasons to start the FastDiet. You may be inspired by your sister or your best friend, your dad or your doctor. You may have decided you want to cut your risk of age-related disease. You may want to reduce your cholesterol, boost your brain, improve your mood, lower your blood pressure, lengthen your life.

Or you may just want to look good in a swimsuit.

I say “just.” But looking good and (more importantly) feeling good about your body is no mere vanity project. It can have a real emotional impact on a life. I’m reminded of one FastDieter who told me that, after years of fruitless yo-yo dieting, six months of 5:2 had given her enough body confidence to go to the local pool and swim with her young daughter for the first time ever. That’s not vanity. It’s the glorious stuff of life.

Not long ago, a magazine survey found that women think about their bodies every 15 minutes (which is, apparently, more than men think about sex). There are times of the year, of course, when we put ourselves under greater scrutiny still. On the beach, in summer, in our shorts and bikinis, we think about the shape we’re in even more often—a constant background hum, the helicopter moaning overhead. Men may not go on about it quite as much, but they tend to be just as aware as T-shirt weather creeps up to ambush those hibernating pecs and paunches.

So now is the time to act. The beach beckons and this is your call to arms. The most challenging weeks of the year may be looming on the sun-kissed horizon, but that’s no reason to bury your head in the sand or collapse into a kaftan for cover. We have a plan. It is called the FastBeach Diet. Think of it as “5:2, the Next Generation.” It promises to shake things up, with a wealth of new tips, tricks, and takes to help you break the plateau, make the leap and reboot your 5:2 for summer. In the words of the late, great Janis Joplin, we’re gonna try . . . just a little bit harder. But first, let’s recap on the original FastDiet—what it is and how it works.
What Is the FastDiet?
It may be radical, but the FastDiet is also wonderfully economical with its rules. I like that The Times has called it the “haiku diet”—a pithy, almost poetic agenda. All you really need to know is that:

• You eat normally for five days a week and then, for the other two days, you consume a quarter of your normal calorie intake—around 600 calories for men, 500 for women. So, it is not total “fasting,” but a modified version.

• It is not continual fasting, but intermittent. Our experience is that nonconsecutive Fast Days work best, though you can do them back to back if you prefer.

• Most people divide their calorie allowance between breakfast and an evening meal, aiming for a lengthy “fasting window” between meals. But you can skip breakfast and have a more substantial evening meal containing your whole calorie quota if it better suits your day.

• It does matter what you eat on a Fast Day: plan your calorie quota by sticking, as the recipes in chapter 7 do, to the FastDiet mantra: “Mostly Plants and Protein.” That way, you’ll stay full longer and get adequate nutrients in your diet.
Why 5:2?
In the beginning, Michael tried several different fasting regimens; the one he settled on as the most realistic and sustainable was five days off, two days on, which meant that the majority of the time was spent free from calorie-counting. On this program, in 12 weeks Michael lost more than 20 pounds of body fat and his blood glucose fell to a healthy level. I lost 22 pounds and returned to my pre-motherhood body weight (and, more importantly, shape).

That was only a little over 18 months ago. We’re still learning about the true long-term benefits of IF, and we don’t, as yet, have a comprehensive account of potential pitfalls, particularly why some people flourish on 5:2 and others may find it harder. It may be that there is no “one size fits all.” What we do know is that thousands of people have followed the FastDiet, lost weight, gained health, and found it surprisingly sustainable, effective, and life affirming. New studies are underway and we hope to bring together the latest thinking in a fully updated new edition to be published in 2015.
So Where’s the Catch?
Really, there isn’t one. The FastDiet, don’t forget, is simply a modern take on an ancient idea. Fasting, in one form or another, has been practiced for centuries by most of the great religions, and if done properly seems to be extremely safe. There is no evidence of significant side effects (though some people may experience headaches and constipation, particularly at first; these can generally be prevented by drinking lots of water or calorie-free fluids, such as black coffee and herbal tea, and eating foods rich in fiber).

Indeed, the FastDiet has helped to debunk some of the myths that have developed around the way we eat in the West—for instance that:

• You need to eat whenever you feel hungry.

• Eating every few hours will increase your metabolic rate.

• If you don’t eat every few hours your blood sugar will fall and you will feel faint.

None of these widely held beliefs is backed by science. You will discover that short bouts of hunger are manageable and soon pass. Similarly, there is no metabolic advantage to spreading your calories over the day, nor is there any evidence that short periods without food will cause your blood glucose to plunge to seriously low levels. Most nights, don’t forget, you happily go 12 hours without eating, and many people feel fine with a late breakfast, especially on a Sunday when the start can be in delicious slow-motion.
Should You Be Skeptical?
Michael and I certainly were. After all, anyone who has ever gone on a conventional diet knows that they are hard work; they may deliver results in the short term, but then life gets in the way—we’re soon bored and the weight creeps back on. We’ve found, however, that the 5:2 FastDiet does work—for exactly the reason that other diets don’t: there is none of the boredom, frustration, or serial denial that characterises standard diet plans; eating is still a pleasure; there’s no cutting of food groups, no pathologizing of eating. And indeed, even the turbo version laid out here is full of forgiveness, generosity of spirit, and the crucial adaptability required to fit it into a busy life.
A Word on the Benefits of Intermittent Fasting
The reason behind IF—briefly but severely restricting the number of calories you consume—is that it “fools” your body into thinking it is in a potential famine situation and that it needs to switch from go-go mode to maintenance mode. Fasting is the shock that resets the clock. Its many benefits include:

• Fat loss of 1–2 pounds a week

• A reduction in a hormone called IGF-1, which means that you are reducing your risk of a number of age-related diseases

• The switching on of repair genes

• Improvements in cardiovascular health and cholesterol levels

• A rest for your pancreas, boosting the effectiveness of the insulin it produces in response to elevated blood glucose

• Metabolic changes that tweak your body into burning fat and increase its insulin sensitivity; this in turn will reduce your risk of obesity, diabetes, heart disease, and cognitive decline

• Increased levels of neurotrophic factor in the brain, which should make you more cheerful, even when contemplating your summer swimsuit
The FastDiet and Weight Loss
While clinical studies into IF in general, and 5:2 in particular, are still in their early stages, there’s a great deal of convincing anecdotal evidence that the approach can be startlingly effective for many people. Anecdote, as Michael often says, makes poor science, but it does tell a story. Many thousands of people have adopted the plan and witnessed significant improvements in their weight, cholesterol, and general health, and have gone on to post their success stories online (we have included just a fraction of these in the testimonials chapter at the back of this book). We regularly meet people on the street and see friends and family who’ve lost weight and gained health. My father, for instance, has lost 56 pounds over the course of a year on the FastDiet. That’s about the weight of an eight-year-old child. I can now get my arms all the way around him when we hug hello. It’s a seismic change, and a joy to behold.


What people sometimes forget in their drive to “lose weight” is what they really want to lose is not weight as such, but fat. Carrying excess fat is not just a bummer on the beach; it’s bad for your health. Here’s what we know about the effect IF has on fat:

• It achieves a gradual weight loss—and it’s almost all fat.

• It increases fat burn. More of the calories you use for fuel during a fast come from fat stores than muscle. A study from Nottingham University1 found that the proportion of energy obtained from fat rose progressively over 12–72 hours of fasting, until almost all the energy being used was coming from stored fat.

• When we eat, we use the carbohydrates and fat supplied by the food for fuel, instead of tapping into our stored fat reserves. Constant grazing may be what’s keeping fat from being burned—and fasting is one way to release it.

• Interestingly, the heavier you are, the more likely it is that fasting will lead to substantial fat loss with muscle being spared.

• A bonus for Intermittent Fasters is that it seems to lead not just to fat loss generally, but specifically to fat loss around the gut—this is the visceral fat and is particularly dangerous because it increases your risk of heart disease and diabetes.

• One reason why it’s important to preserve as much muscle mass as possible is that muscle is metabolically active. Lean tissue burns calories, even at rest.

So Why the FastBeach Diet?
The FastDiet’s unique selling point seems to be its high level of compliance: we do it and we stick with it because most of the time, we’re not thinking about dieting at all. But some fasters want to boost the process at certain times of year. You may be one of those for whom the 5:2 has not proved the magic bullet you hoped for. Others among you may want to nudge yourself off a plateau and budge any reluctant pounds that are hanging on despite your adherence to 5:2.

I’ve written this book to be used as a primer for the summer holidays; the idea is to start the six-week regimen in May, June, or July, in good time for take off (that’s clothes, not planes). The longer, brighter days and fresher produce of late spring and early summer make it an ideal time to embark or improve upon a weight-loss program. And, as we’ve already established, there’s nothing like an approaching bikini—or T-shirt—to make you think twice about that piece of pie.

That said, the principles of the turbo-driven 5:2 diet laid out here are applicable at almost any time of the year. You might like to use its additional hints and ideas if you are preparing to get married, if you have a big event coming up, if you’re starting a new phase in your life, if you’re ready to lose some baby weight, or if you’ve had a particularly sedentary and glutonous couple of months (after Christmas perhaps).

You may, of course, be coming to The FastBeach Diet cold, without having read or acted upon the original book. This book is an adjunct. Think of it as a boot camp for the 5:2. It is a condensed, modified program of greater intensity with the aim of helping you achieve a reasonable target weight in a six-week period. Note now that on the FastBeach Diet, you will be encouraged to step it up—to get a bit tougher, a bit bolder, with your FastDiet. But this extra commitment is intended to be short-lived. Just a bit more effort. For just six weeks.
Why Six Weeks?
In truth, the six-week figure is fairly arbitrary. I have used my own experience and a 25-year career in the fashion and fitness business, together with what I have learned from many other dieters, to come up with a reasonable period during which I believe the average individual—someone with a little willpower and plenty of good intentions—can commit to and concentrate on a more intense 5:2 regimen. It hinges on attention span and compliance; six weeks should be enough time to see measurable results without boredom setting in. It’s also, by happy coincidence, about the length of time we usually give ourselves to prepare mentally and physically for our summer vacations . . . the Six-Week Sprint to the pool.

You may choose to extend the FastBeach Diet, perhaps to two months. But be clear: it is only meant to be a short-term option; afterwards, you should return to the classic FastDiet rules, without undue concern for calories on a non-Fast Day. Remember: it is this flexible and sociable foundation that lends the FastDiet its psychological advantage.

If the FastBeach Diet seems unnecessarily faddish to you, or if you’re not keen on a “fast-fix” message, if you treasure the absolute simplicity of the original FastDiet—well, I empathize and understand. Just stick with your original 5:2 FastDiet. This book is aimed at people who want a short-term booster plan to get them from A (the sofa) to B (the beach) by undertaking a reasonable but more vigorous protocol. It’s not designed to be a “forever plan” like the 5:2. It’s the FastDiet, just a bit faster. So are you in? Here’s what to expect . . .

The FastBeach Diet includes:

• A clear six-week plan to encourage fat loss

• Plateau-busting techniques to jump-start the 5:2 and make it work for you

• Mindfulness methods to help you tough out a fast and eat with understanding every day

• Habit-changing ideas to sharpen up on non-Fast Days

• A High Intensity Training (HIT) exercise program for fitness and fat loss, achievable in just a few minutes a day

• Lots of brand-new, calorie-counted summer recipes, with plenty of healthy, speedy ideas for busy days

• Motivation, meal plans, and 5:2 support to rev up your FastDiet and help get you beach fit for summer
When Should You Start?
If you do not have an underlying medical condition, and if you are not an individual for whom fasting is proscribed (see the disclaimer on this page), then there really is no time like the present. But first, a bit of prep.

About The Author

Photograph © Alisa Coonan

Mimi Spencer is a feature writer, columnist, and the author of 101 Things to Do Before You Diet. 

Product Details

  • Publisher: Atria Books (June 24, 2014)
  • Length: 176 pages
  • ISBN13: 9781476790398

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Raves and Reviews


“A nice narrative introduction to HIIT... excellent practical advice on how get started with ‘Fast Exercise’ and some really nice tips on how to keep going... informative, easy to understand... offers not only good health but a host of spillover benefits besides... Fast Exercise is the way of the future.”

– Professor Stuart M. Phillips, Ph.D., FACSM, FACN

“A great practical introduction into the field of high intensity exercise. The personal perspective matched with references to the both old and new scientific literature provides compelling reading.”

– Carl Johan Sundberg, MD, PhD, Professor, Dept. of Physiology & Pharmacology, Karolinska Institute, Stockholm, Sweden


"A health revolution."

– The New York Times

“The biggest diet revolution since Atkins.”

– Daily Mail

“Fans of the FastDiet report becoming radically healthier by fasting two days a week.”

– Good Morning America

“The only diet you'll ever need.”

– Mail on Sunday

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