Extrait
CHAPTER 1
WHY MOST DIETS FAIL
The second day of a diet is always easier than the first. By the second day, you're off it.
—JACKIE GLEASON
If you're trying to lose weight, the last thing you need is another book that tells you to eat less and exercise more—you already know that. Except for the very small minority of people whose metabolism lets them eat whatever they want and never gain a pound, you're going to have to burn more calories than you take in if you want to lose weight. Furthermore, once you hit that magic number, you'll have to keep your activity level up and your calorie intake down, or you'll be back at square one before you know it.
Yet these are the two stumbling blocks in virtually every weight loss endeavor, whether it's a plan you've read in a book or online, a commercial program, or you're simply going it on your own. You get hungry or you feel the diet is overly restrictive, so you cheat or give it up altogether. Regular exercise is too time-consuming or too boring, and you stop working out. Once again, you're disappointed with the promises of easy weight loss that didn't pan out. Above all, you're disappointed with your own failings.
Don't be too hard on yourself. Being overweight doesn't mean you're self- indulgent, lazy, or undisciplined. Obesity isn't a character flaw. If you eat too much and find it a chore to lace up your walking shoes, you're just following your natural instincts.
IT'S NOT YOUR FAULT
For millions of years, our ancestors were hunters and gatherers. Because they endured cycles of feast and famine, survival depended on seeking out the most high-calorie, energy-dense foods available—and when they were fortunate enough to find them, eating like there was no tomorrow. Thus, we are genetically programmed to be attracted to and indiscriminately eat calorie-rich fare.
Animals' eating habits are also dictated by their DNA, so why aren't they fat? Imagine the spectacle of squirrels in your local park with puffy cheeks and potbellies so big they can't even climb trees. Squirrels and other animals in the wild aren't thin and lively because they're disciplined. It's because the effort required for them to obtain food has remained more or less constant throughout history. With domesticated animals, it's a different story. Siamese cats and cocker spaniels did not evolve on a diet of table scraps and canned meat, and survival required more than moseying over to the food dish a couple of times a day. But that's the situation most household pets find themselves in today, and as a result, half of the dogs and cats in this country are obese.
It's the same with humans. Until the relatively recent past, food was scarce, and high-calorie foods were few and far between. A great deal of physical effort was required to get enough calories to stay alive, let alone to gain excess weight. The modern world is a radical departure from that environment. We no longer have to hunt or gather, unless you consider shopping for groceries "gathering." In fact, food practically stalks us! It beckons us from our fridges and cupboards, the break room at work, drive- thrus and shopping centers, in magazines and on TV. Everywhere we turn we're enticed by the sights and smells of food.
And much of it is high-calorie fare—precisely what we are hardwired to want. If you had to choose between a bountiful salad and a bowl of rocky road ice cream with whipped cream on top, which would you find more attractive? If you are honest and go for the ice cream as most would, you're simply following your genetic impulses to maximize your caloric intake. Some experts like to pin the obesity crisis on food manufacturers for providing fatty, sugary, processed foods or on restaurants for serving supersize portions. But these businesses would go broke if all they offered was spinach and tomatoes. They're just giving us what we want.
I could make a similar case for exercise, or rather the near universal aversion to exercise. I'm not saying our DNA promotes laziness, but there is an inborn drive to conserve energy. It's human nature to do what needs to be done and not much more. The tendency for most people—whether it's work, chores around the house, or physical activities--is to do just enough to get by. If a task that requires exertion isn't motivated by reward or punishment (exercise is a prime example), it's less likely to get done.
If you want to see our natural, calorie-maximization, energy-conservation instincts in action, go to an all-you-can-eat buffet, or sit down to a holiday dinner. Watch cars circle around a store's parking lot as drivers jockey for spots near the entrance, or count the number of people who take the stairs versus an escalator. To gauge the impact of these behaviors, visit the mall, a sporting or cultural event, or another public gathering, and take a look at the crowd. Two-thirds of the people walking around have a weight problem.
WHAT WE EAT
Between 1971 and 2000, our average daily caloric intake increased by 335 calories for women (1,542 to 1,877) and by 168 for men (2,450 to 2,618).1 Since then, calorie counts have remained relatively stable and may have even decreased a bit. There's also been a slight decline in the percentage of total calories from carbohydrates, although it still hovers at around 50 percent, with 16 percent from protein and 34 percent from fat.2 The most significant dietary change over the past 4 decades is that we are getting more and more of our calories from added sugars, fats, soft drinks, and "mixtures of mainly grain" in "prepared, frozen, and take-out meal combinations"3—high-calorie foods that pack on the pounds, wreak havoc on blood sugar levels, and make losing weight all the more difficult.
* SoFAS = solid fats and added sugars
Note: Bars show average intakes for all individuals (ages 1 or 2 years or older, depending on the data source) as a percent of the recommended intake level or limit. Recommended intakes for food groups and limits for refined grains and solid fats and added sugars are based on amounts in the USDA 2,000-calorie food pattern. Recommended intakes for fiber, potassium, vitamin D, and calcium are based on the highest AI or RDA for ages 14 to 70 years. Limits for sodium are based on the UL and for saturated fat on 10% of calories. The protein foods group is not shown here because, on average, intake is close to recommended levels.
Based on data from: U.S. Department of Agriculture, Agricultural Research Service and U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. What We Eat in America, NHANES 2001-2004 or 2005-2006.
Bottom line: Don't beat yourself up if you're overweight. It's not your fault. Just recognize that because losing weight requires you to work against your natural instincts, it's going to take a little more effort and discipline on your part--which is why you need a scientifically proven, patient-tested, no-gimmicks guide like the Mini-Fast Diet.
THE DIET INDUSTRY: WHAT WORKS?
At any given time, 75 million Americans are dieting, and there is no shortage of offers to help. According to the latest edition of The U.S. Weight Loss & Diet Control Market, published by Market-data Enterprises, we are expected to spend $66.5 billion per year in our quest to get thin.4
The weight loss market includes commercial programs such as Weight Watchers, Jenny Craig, and TOPS (Take Off Pounds Sensibly), and medically supervised clinics that specialize in weight reduction. It encompasses prepared foods from companies such as Nutrisystem, as well as meal replacement shakes and bars from Slim-Fast and dozens of other manufacturers. There are books that tell you how to drop pounds by eating low-carb with plenty of meat, or by going high-carb vegetarian or vegan. You can diet according to your blood type, your metabolic type, and even your zodiac sign, or you can eat like a caveman, a Frenchwoman, or a movie star. Cabbage soup, grapefruit, apple cider vinegar, lemonade, beer, cookies, chocolate—the range of weight loss angles out there is truly remarkable.
What if I were to tell you that you could lose weight on most any diet? It's true, provided that you actually follow the diet. Regardless of the hook or gimmick, virtually every plan has one thing in common: They all require you to eat fewer calories (yes, even the chocolate and cookie diets). I'm not saying that they're all equally nutritious or advisable, only that the crux of weight loss, for most people, is calorie restriction.
Proponents of various programs will say that their way is the only way, and they may even be able to produce evidence to back up their claims. But, remember, just because someone's brother lost 30 pounds on one diet, or a celebrity slimmed down on another, isn't proof positive—few of these approaches have ever been subjected to scientific scrutiny. Yet the studies that have been conducted demonstrate that a variety of diets do indeed work, at least over the short term.
One representative study is a British clinical trial that compared four well-known programs: the Atkins low-carb diet, Slim-Fast's regimen of low-calorie meal replacements, Weight Watchers' point system for calorie control plus weekly meetings, and Rosemary Conley's regimen of a low-fat diet and weekly group exercise classes, which is popular in the United Kingdom. Researchers enrolled 300 overweight or obese participants, assigned equal numbers to each program, and followed them for 6 months.
All of the participants lost a similar amount of weight and body fat regardless of the diet they were on. The average loss was 13 pounds total and 9 pounds of fat. The group following the Atkins diet lost more during the first 4 weeks, but the other approaches were equally effective over the 6-month study period.
The Rest of the Story
Here's the rest of the story. These people had every chance of success. As with all clinical trials, the selection process was arduous. The volunteers had an excellent support system and were communicated with regularly, as often as once a week for those in programs that included meetings or classes. They were reimbursed for classes, books, meal replacements, travel expenses, and other related costs, and they were offered a free diet of their choice at the study's conclusion. Yet 28 percent dropped out of the study. They claimed that the diet was intolerable. They weren't losing enough weight. Or they simply stopped showing up. Whatever the excuse, more than a quarter of these highly motivated, well-supported people couldn't stay on a diet for 6 months.
Even more telling, participants were asked to be reevaluated 6 months later. Only 54 percent complied with this request, and at that point their dieting behavior had changed dramatically. Fewer than half were still on their original diets; the others had swapped programs or were dieting on their own. (More people stuck with or switched to the group-based approaches.) At the end, 20 people remained in Weight Watchers, 20 in Rosemary Conley, 9 in Atkins, and 9 in Slim-Fast. Although these small numbers limit statistical analysis, the researchers concluded that individuals who stayed with a diet for 1 year sustained an average weight loss of 10 percent of their initial body mass.5
Similar results were seen in a 2-year study published in 2010. Researchers from Temple University in Philadelphia pitted a low-fat diet against a low-carbohydrate one, both in combination with an intensive lifestyle modification program that included regular exercise and group support. The average weight loss on both diets was nearly identical, about 11 percent of baseline at 6 and at 12 months. After 2 years, however, some of the weight had crept back on, and at the study's conclusion, the mean loss was 7 percent. In this study there also was a fair amount of falloff. After a year, about a quarter of participants failed to return for assessment, and at the 2-year mark, 32 percent of the low-fat group and 42 percent of the low-carb group had dropped out.6
Let's push that date out 4 or 5 years. How successful are dieters at that point? The data is pretty grim. When a research team at UCLA reviewed 31 studies of long-term outcomes of various calorie-restricting programs in order to determine which were the most effective, they found that up to two- thirds of the dieters had regained more weight than they lost while dieting.7 You don't need a scientific study to tell you this. You've probably seen it among your circle of friends, and certainly with the celebrities whose weight fluctuations are mercilessly chronicled in the media. No doubt about it, long-term weight maintenance is tough.
WHAT ABOUT DRUGS?
Weight loss is the holy grail of the pharmaceutical industry. Who wouldn't love to stay skinny simply by popping a pill? Just imagine the sales! So far, Big Pharma has failed to come up with a medication that's both effective and safe.
You may remember fen-phen, a drug combo (fenfluramine and phentermine) that was taken off the market in 1997 after it was linked with increased risk of heart valve problems and pulmonary hypertension. Because the cardiovascular issues were actually associated with fenfluramine, phentermine is still available as an appetite suppressant. It can take the edge off hunger, but its efficacy levels off over time, there's a potential for addiction, and it has numerous adverse effects, including increased blood pressure and heart rate. Fat blockers are another class of weight loss meds. Orlistat (Xenical and Alli) inhibits enzymes that digest fat, causing about 30 percent of the fat you eat to pass through the intestinal tract rather than being absorbed. Not surprisingly, these medications are notorious for unpleasant side effects such as diarrhea, gas, oily spotting on underwear, and difficulty controlling bowel movements, as well as impaired absorption of fat-soluble vitamins.
In 2012, the FDA approved two new weight loss drugs: Qsymia (a combination of phentermine and topiramate, an anticonvulsant medication) and Belviq (lorcaserin, an appetite suppressant). These drugs have numerous side effects—and both were rejected earlier due to safety concerns. Don't hold your breath waiting for a pill that enables you to eat whatever you want and never gain weight. The benefits of all diet drugs are modest, and this approach does nothing to improve long-term weight management.
I'm not telling you this to discourage you or to disparage other programs; rather, I'm simply trying to inject a dose of reality into the diet debate. There's a saying, "The best diet is the one you stick to." But as these studies—and, most likely, your personal experience—illustrate, that's the problem. It may not matter which program you select or what combination of fat, protein, and carbohydrate you eat, but your compliance with your chosen program is of the utmost importance.
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