The
Advanced Mediterranean Diet:
Lose Weight, Feel Better, Live
Longer
2nd Edition
Steve Parker, M.D.
***
Published
by Steve Parker / pxHealth
Smashwords Edition
ISBN
978-0-9791284-1-7
Copyright 2012 Steve Parker
This book is
available in print at most online retailers
***
Smashwords Edition, License Notes
This ebook is licensed for your personal enjoyment only. This ebook may not be re-sold or given away to other people. If you would like to share this book with another person, please purchase an additional copy for each recipient. If you’re reading this book and did not purchase it, or it was not purchased for your use only, then please return to Smashwords.com and purchase your own copy. Thank you for respecting the hard work of this author.
***
Dedication
Disclaimer
Preface
to the Newly Revised and Updated Edition
Introduction
Chapter
1: Why We Eat and What Happens Next
Chapter
2: I’m Fat. So What?
Chapter
3: A Philosophy of Weight Loss
Chapter
4: Two Diets: Moderate and Radical
Chapter
5: Ketogenic Mediterranean Diet
Chapter
6: Daily Life With Low-Carb Eating
Chapter
7: Advanced Mediterranean Diet
Chapter
8: Recipes for the Ketogenic Mediterranean Diet
Chapter
9: Recipes for the Advanced Mediterranean Diet
Chapter
10: What? Me Exercise?
Chapter
11: Long-Term Maintenance and Prevention of Weight Regain
Recommended
Further Reading
Selected
References by Topic
Recipe
List
About
the Author
Other
Books by Steve Parker, M.D.
Connect
With the Author
To those working in the weight-management field who value truth above personal profit
The ideas and suggestions in this book are provided as general educational information only and should not be construed as medical advice or care. All matters regarding your health require supervision by a personal physician or other appropriate health professional familiar with your current health status. Always consult your personal physician before making any dietary or exercise changes. The publisher and author disclaim any liability or warranties of any kind arising directly or indirectly from the use of the Advanced Mediterranean Diet and the Ketogenic Mediterranean Diet. If any problems develop, always consult your personal physician. Only your physician can provide you medical advice.
The names in patients’ cases discussed herein have been changed to protect their identities.
Preface to the Newly Revised and Updated Second Edition
Since publication of the first edition in 2007, medical and nutrition scientists have made several watershed advances in our understanding of optimal nutrition and weight management. This second edition incorporates that new knowledge, along with other important eye-opening research results.
The most astounding new scientific findings are that the saturated fat and total fat content of our diets do not cause or contribute to heart and vascular disease. The same is true for cholesterol in our food. In other words, foods that contain fat, saturated fat, and cholesterol don't cause us to have heart attacks, strokes, or hardening of the arteries (atherosclerosis), or high blood pressure. These statements apply to a large majority of people, although there may be rare exceptions.
This new knowledge, which is accepted by most experts in medical nutrition science, runs counter to popular thought and teaching of the last four decades. At the same time, it's true that the information hasn't yet trickled down to many physicians and dietitians working in the trenches of clinical care. The scientific supporting literature is listed at the back of the book in the Selected References section.
The second earth-shaking development is the discovery that certain carbohydrates are particularly prone to make us gain excess fat weight, and that avoiding those carbohydrates can be especially helpful in weight management. This is best demonstrated by numerous scientific studies that document more successful weight loss in dieters who drastically reduce consumption of carbohydrates, at least for the short term. The idea that carbohydrates are uniquely fattening applies to a majority of people, but certainly not all. The scientific supporting literature is listed at the back of the book in the Selected References section.
These advances led me to design a very-low-carbohydrate version of the Mediterranean diet, included herein as the Ketogenic Mediterranean Diet. The original Advanced Mediterranean Diet is also here, modified to allow more total and saturated fat. You choose which diet you wish to follow, depending on your needs, proclivities, and personal metabolism. Or use both diets at different times.
The first edition of The Advanced Mediterranean Diet noted numerous health benefits to eating Mediterranean style, including increased longevity and reduced rates of heart disease, stroke, dementia and cancer of the colon, breast, prostate, and uterus. Studies published over the last five years have expanded the list of health benefits even further, to include prevention of type 2 diabetes and stomach cancer, for example.
To lose excess weight, you've got to exercise a lot, right? That's now old school thought, and not really true. The latest research tells us that, in general, exercise contributes only minimally to successful real-world weight loss. "Real world" as opposed to The Biggest Loser TV show. And what's a minimal contribution to weight loss? About 10%. What about exercise's role in long-term weight management? That's a whole 'nother can o' worms.
THE KEY TO WEIGHT MANAGEMENT
I will assume that you're overweight and reading this book to lose weight. My goal is to share with you the information that has helped my personal patients lose weight effectively, safely, and permanently. Reduction of excess body fat has been particularly critical for my patients with diabetes, high blood pressure, heart problems, strokes, low back pain, and lower limb arthritis. Even if you're essentially healthy, you may need to lose 10 to 50 pounds (4.5 to 23 kg) in order to feel and look your best.
The standard medical approach to weight loss too often is:
- a five-minute
lecture on proper eating and exercise habits
- presentation of a
confusing, unrealistic, calorie-restricted diet pamphlet
-
occasional referral to a dietitian
- follow-up office visits with
focus more on the medical problem than the weight problem.
But this approach nearly always fails, and those few who do lose weight typically regain it within a few weeks or months. The reasons for failure of weight loss programs are numerous and complex, but they share a unifying characteristic: lack of knowledge.
We need adequate knowledge of nutrition and how our bodies work to avoid wasting time, money, and energy on worthless weight-loss schemes. We must learn to easily identify weight-loss plans that are designed only to enrich the entrepreneur. We must learn to recognize scams that may jeopardize our physical and emotional health. Most importantly, knowledge is your key to successful long-term weight management. Given an adequate knowledge base, most people don’t need to consult physicians, dietitians, or other advisers on weight loss.
Acquisition of that knowledge base, however, is not easy. Information and opinions are readily available from the Internet, books, television, magazines, newspaper articles, friends, acquaintances, health food store clerks, hearsay at the beauty salon, and advertisements for various weight-loss products. Much of this is worthwhile, much is worthless.
How do you separate the wheat from the chaff? The "doctor" in my doctor of medicine degree is based on the Latin word for "teacher." I'll share with you what your personal physician likely would teach you, if only he had the time. He would help you find the pearls of knowledge in a sea of complexity, confusion, contradiction, and quackery. My aim is to educate you so that you can seize control of your weight problem.
Although some of the information presented here is common knowledge, most of it is gleaned from my three decades of clinical experience with overweight patients and from my analysis of scientific literature generated by obesity researchers and clinicians.
The scientific literature is neither readily available nor understandable to the layperson. Furthermore, technical popularizers in the media tend to sensationalize preliminary research results. They may unwittingly promote fads since they lack the scientific training and clinical experience to recognize the real, but rare, breakthroughs. Having observed my patients’ weight-loss efforts of every description, I know what works and what doesn’t.
ACKNOWLEDGEMENTS
Sir Isaac Newton wrote in 1676: "If I have seen further, it is by standing on the shoulders of giants." He was acknowledging that his scientific success had been built upon the achievements of other scientists. While no one would ever mistake me for a Newton, I am similarly indebted to generations of scientists and physicians who have discovered and shared basic truths in the fields of nutrition, physiology, pathophysiology, and epidemiology. These are the foundations of this book.
I am grateful to Linda Kimmel, medical librarian, for her help acquiring the scientific literature, and to Scottsdale Healthcare for funding her position. I am obliged to innumerable dietitians and nutritionists who generously shared their knowledge with me. I am indebted to my patients, who helped me learn the art and science of medicine through the privilege of caring for them. Thanks to Art Chance for his participation years ago in our two-man think tank dedicated to improving health through exercise and nutrition.
Certain individuals have influenced my ideas about nutrition and fitness over the last few years in a positive way. A partial list (in no particular order) includes Monica Reinagel, Jimmy Moore, Regina Wilshire, Dave Dixon, Douglas Robb, Gary Taubes, Michael R. Eades, Robert C. Atkins, Laura Dolson, Lyle McDonald, Dr. J, Emily Deans, Tom Naughton, Beth Mazur, Sandy Szwarc, Travis Saunders, Peter Janiszewski, Richard David Feinman, Skyler Tanner, Darya Pino, Alex Hutchinson, K. Dunn Gifford, Yoni Freedhoff, Stephan Guyenet, Richard K. Bernstein, Arya M. Sharma, Dan Buettner, Conner Middelmann-Whitney, Jennifer Eloff, Eric Westman, Stephen Phinney, and Jeff Volek. I'm grateful to them for having stimulated my cerebral synapses. Any errors in this book are strictly mine, not theirs.
I thank my immediate family (Sunny, Dan, Brian, Casey, Paul, and Austin) for enduring my nutritional obsession, including recurrent dinner-table discussions of junk food, whole grains, calories, carbohydrates, and fiber. I am especially indebted to my wife for her role as steadfast supporter, sounding board, and Mediterranean chef. I love you, Sweet Pea. I thank God for enabling me to present this information to you. Any good that comes from it is from Him.
"I’ve become my mother!" cried Janice as she studied her reflection in a full-length mirror on her 40th birthday. She had ballooned from 130 to 175 pounds (59 to 80 kg) over the last 15 years. Janice didn’t think twice about her weight until after her first baby, Ashley, was born when Janice was 24. She gained 30 pounds (14 kg) during the pregnancy, but was down 15 pounds (6.8 kg) by the time she left the hospital. The other 15 pounds, which she called baby fat, hung around. During her teen years, Janice had been active in her school’s marching band and regularly played softball. She jogged two or three miles a couple days per week, just to keep in shape for her beloved softball.
After Ashley was born, Janice still played softball, but couldn’t find the time to jog. Her second child, James, was born two years after Ashley. Household life began to get hectic. Janice’s husband was working 60-hour weeks at the tire store. Her mother, 40 pounds (18 kg) overweight, remarked how hard it was to chase Ashley around the house when she babysat. Janice decided to table softball until the kids were older.
Janice added another eight pounds of lingering baby fat while pregnant with James. She got a job at a call center six months after his birth. She sat most of the day, processing orders for various products. The family’s evening meal, by necessity it seemed, was too often a sack of fast food she picked up on the way home. Janice didn’t have the time or energy for exercise after cleaning, shopping, and laundering. She drank four cans of Dr. Pepper every day for the pleasure and a boost of energy.
The surgeon who removed Janice’s gallstones at age 35 told her they were caused by her excess weight. She began to worry about other health effects and her lack of energy and stamina. Years after giving up softball, she tried jogging around the block just once and strained her right hamstring muscle. No more jogging for her, she decided.
Over the next five years, Janice tried many of the popular diets: low-fat, Atkins, cabbage soup, NutriSystem, Jenny Craig. They all worked great. For a while. She lost eight to 15 pounds (6.8 kg) , then lost her enthusiasm. Two months later she would be back up to her baseline weight, if not higher.
Since breast cancer runs in her family, Janice came to me for a routine physical and referral for a mammogram. At the end of our visit, she asked, almost as an afterthought, "Hey, doc, what can I do to get this weight off?" It was the end of my workday so we had time to chat. She shared her frustration with her prior weight-loss efforts. She told me her dream of fitting into some of her old clothes and wondered if her husband would ever again look at her the way he did when they were newlyweds. She mentioned the stress and time constraints of a two-teenager household, and how the teens would eat only two kinds of food: fast food and junk food. She told me how it hurt when she had to turn down the school’s request to chaperone her son’s four-mile nature hike with his class; she knew she just didn’t have the stamina.
I shared with Janice my own frustration in dealing with my patients’ medical problems that were caused or clearly aggravated by their excess weight. I saw hundreds of patients like Janice give their honest and best efforts to lose weight and keep it off, only to fail. Their medical problems were good for my business, but I longed for better outcomes for my patients. I had seen weight-loss methods of all kinds come and go, then come again. Surely, there had to be a better way. I vowed to review the situation comprehensively, to learn definitively what we should be eating and doing, and to share with Janice the results of my efforts. In these pages, you'll see what I discovered.
BASIC STATS
Sixty-six percent of adults in the United States are chubby, pudgy, portly, plump, rotund, stout, corpulent, or just plain fat. These adjectives fall somewhere on the spectrum from mildly overweight to morbidly obese. Overweight means having more adipose tissue (commonly known as fat) than is considered healthy or normal by historical standards. Obesity refers to the more extreme accumulations of fat. Of the 66% of us who are overweight or obese, about half are overweight and half are obese.
A healthy weight for a 5-foot, 4-inch person (163 cm) would be 108 to 145 pounds (49 to 66 kg); obesity starts at 175 pounds (79.5 kg). For someone 5-foot, 10-inches tall (178 cm), a healthy weight is 128 to 174 pounds (58 to 79 kg), with obesity starting at 208 pounds (94.5 kg).
Have you ever noticed in old photographs how everyone seemed so skinny, even gaunt? The pictures don’t lie. In fact, photos tend to make us look heavier. Despite a barrage of popular media reports touting exercise, healthy lifestyles, and low-fat eating, the prevalence of adult obesity in the United States increased from 13% of us in 1960 to 34% in 2010. That's one in three.
And our children (ages 6-19) are learning by example: 19% - that's one in five kids - are now overweight, gradually rising over the last three decades.
About 30% of of men and 45% of women in the United States are dieting currently, either in pursuit of culturally ideal attractiveness or health and longevity.
WHAT CAUSES OVERWEIGHT?
It's complicated. I don't want to bore you with too many details, so here's a simplified explanation.
Overweight can be defined simply as excessive storage of energy in the form of fat. To some extent, it's the result of an imbalance between energy intake and energy expenditure. Energy intake is food. Energy expenditure is a combination of physical activity and metabolism.
Metabolism refers to the complex chemical and physical processes in our bodies that are necessary for the maintenance of life. In metabolism, some substances are broken down to produce energy for vital processes, such as breathing, blood circulation, and generation of body heat. The other side of metabolism is formation of vital substances and structures, as in tissue repair or blood production. When more energy (food) is put into the system than is necessary for metabolism and physical activity, the excess is stored as fat. That fat is available to produce energy just as the wax in a candle is burned to release its stored energy as light and heat. Indeed, some candles are made from fats (tallow).
The fine balance between energy intake and expenditure is influenced by numerous factors, including heredity, environment, psychology, and basic physiologic mechanisms.
INSULIN: THE FAT-BUILDING HORMONE
Insulin is a major hormone influencing fat accumulation. In response to eating carbohydrates (and proteins to a much lesser extent), the pancreas secretes insulin into the bloodstream to lower blood sugar levels that rise in response to digestion of carbohydrates. If we eat too many carbohydrates, the resulting blood sugar will be converted to fat tissue. Eating fewer carbohydrates lowers the amount of circulating insulin, which could help with weight management. More on this later.
HEREDITY
Studies documenting an association between heredity and obesity have lead to unnecessary discouragement of dieters. If your genes totally determine your degree of fatness, it would indeed be a waste of time fighting heredity. Accept your fate and pig out! But genes are only a piece of the puzzle. Note that Japanese-American men living in Hawaii and California are 15 pounds (6.8 kg) heavier and two to three times more likely to become obese than are their counterparts remaining in Japan. Furthermore, the prevalence of obesity in the United States has doubled since 1900. These data speak more in favor of environmental and cultural influences since the gene pool does not change nearly that fast.
AGING
In the United States, both men and women tend to gain excess fat weight from early adulthood to middle age, with body weight peaking around age 50 or 60. Doubtless, we tend to be less physically active as we get older, and therefore "burn" fewer calories (units of energy). It's also true that the rate of metabolism slows by 2% per decade in adulthood. If food intake doesn’t diminish comparably, weight gain results. One-third of us are able to buck the weight gain trend.
ANCESTRY AND THE THRIFTY GENE HYPOTHESIS
Throughout most of human history, mere survival required a great expenditure of energy in the form of physical activity. Our forebears struggled to find and collect food, build shelter, and make clothing. Firewood for heat, cooking, and light was gathered piece by piece. Potable water was not available at simply the flick of a wrist.
In prehistoric days, abundant food was available sporadically and seasonally, if at all. Lacking refrigeration or other effective means of food storage, our ancestors gorged when they had the chance. Their goal was storage of food energy in the one place available to all: fat tissue. Those who could store more energy (fat) were more likely to survive the hardscrabble times when food was scarce due to poor weather, wildfires, disease, and competition. Survivors had genes that facilitated fat storage. For better or worse, they passed these genes down to us.
With the advent of the Neolithic Agricultural Revolution some 10,000 years ago, we became less dependent on the whims of nature. Crop cultivation yielded a steadier and larger supply of food while requiring less work. A few individuals, now with a bit of free time and excess energy, began the development of the arts, philosophy, music, science, and technology.
The Industrial Revolution of the late 18th century then freed the rest of us (in the developed world) from the constant, energy-draining struggle for mere survival. Scientific and technological advances afforded us the basic necessities of life with less physical labor. In 1900, well over two-thirds of the American work force was in farming; today fewer than 2% of us farm. Individuals can now expend yet more effort on intellectual pursuits, such as expansion of our knowledge base and further technological advances. We even have the time and energy for stamp collecting, surfing, bird-watching, fiddling, TV watching, and other such frivolities.
Whereas our ancestors spent untold hours and energy gathering fruit and berries or hunting game, we have labor-saving devices that wash our dishes and change our TV channel for us. Imagine how much more energy we would expend if not for refrigeration, plumbing, electricity, cars, computers, and telephones! As more machines and technology do our work, we require less food energy (calories). In reality, Americans eat more calories than we did 30 years ago.
In a nutshell, our increasingly prevalent overweight problem stems from a biological predisposition to store excess energy as fat, coupled with our sedentary lifestyles and abundant food. Compared to our Paleolithic ancestors, we have incredible access to grains, concentrated sugars, and vegetable or seed oils (such as corn and soybean oil).
If we just look at the last 100 years, we find our diets in the U.S. have changed dramatically. For example, refined sugar consumption in the U.S. was 11 lb (5 kg) in the 1830s, rising to 155 lb (70 kg) by 2000. Over the last 30 years in the U.S., consumption of sugar-sweetened beverages has increased from 3.9% of total calories to 9.2%. In that same time span, the percentage of overweight or obese American adults increased from 47% to 66%. The obesity percentage alone rose from 15 to 34% of adults.
Furthermore, soybean oil consumption increased from essentially zero a century ago to 7.4% of total calories today. Check the ingredients on processed food labels and there's a good chance you'll find soybean oil.
A RADICAL THEORY OF OBESITY FROM GARY TAUBES
At the start of my medical career three decades ago, many of my overweight patients were convinced they had a hormone problem causing the weight gain. I carefully explained that a hormone is rarely to blame. As it turns out, I may have been wrong. The hormone is insulin.
Science writer Gary Taubes has popularized what I'll call the "carbohydrate/insulin theory of obesity" in his 2007 masterpiece, Good Calories, Bad Calories. For details, the average consumer is better off reading his 2011 book, Why We Get Fat.
Mr. Taubes says, "We don’t get fat because we overeat; we overeat because we’re getting fat." Read that again and let it sink in. We need to think of obesity, says Taubes, as a disorder of excess fat accumulation, then ask why the fat tissue isn’t regulated properly. A limited number of hormones and enzymes regulate fat storage; what’s the problem with them?
Mr. Taubes makes a great effort to convince us the old "energy balance equation" doesn’t apply to fat storage. You remember the equation: eat too many calories and you get fat, or fail to burn up enough calories with metabolism and exercise, and you get fat. To lose fat, eat less and exercise more. He prefers to call this the "calories-in/calories-out" theory. He admits it has at least a little validity. Problem is, the theory seems to have an awfully high failure rate when applied to weight management over the long run. We’ve operated under that theory for the last half century, but keep getting fatter and fatter. So the theory must be wrong on the face of it, right? Is there a better one?
Here is Taubes’ explanation. The hormone in charge of fat storage is insulin; it works to make us fatter, building fat tissue. If you’ve got too much fat, you must have too much insulin action. And what drives insulin secretion from your pancreas? Dietary carbohydrates, especially refined carbs such as sugars, flour, cereal grains, starchy vegetables (e.g., corn, beans, rice, potatoes), and liquid carbohydrates. These are the "fattening carbs." Dozens of enzymes and hormones are at play either depositing fat into tissue, or mobilizing the fat to be used as energy. It’s an active process going on continuously. Any regulatory derangement that favors fat accumulation will cause gluttony (overeating) or sloth (inactivity). So it’s not your fault.
If Taubes Is Right, How Do We Lose Excess Fat?
Cut back on carb consumption to lower your fat-producing insulin levels, and you turn fat accumulation into fat mobilization. Especially avoid the "fattening carbs."
Before you write off Taubes as a fly-by-night crackpot, be aware that he’s received three Science-in-Society Journalism Awards from the National Association of Science Writers. He’s a respected, professional science writer. Having read two of his books, it’s clear to me he’s very intelligent. If he’s got a hidden agenda, it’s well hidden.
One example illustrates how hormones control growth of tissues, including fat tissue. Consider the transformation of a skinny 11-year-old girl into a voluptuous woman of 18. Various hormones make her grow and accumulate fat in the places we now see curves. The hormones make her eat more, and they control the final product. The girl has no choice. Same with our adult fat tissue, but with different hormones. If some derangement is making us grow fatter, it’s going to make us more sedentary (so more energy can be diverted to fat tissue) or make us overeat, or both. We can’t fight it. At not least very well, as you can readily appreciate if look at the people around you at any American shopping mall.
If cutting carbohydrate consumption is so critical for long-term weight control, why is it that so many different diets - with no focus on carb restriction - seem to work, if only for the short run? Taubes suggests it’s because nearly all diets reduce carbohydrate consumption to some degree, including the fattening carbs. If you reduce your total daily calories by 500, for example, many of those calories will be from carbohydrates. Simply deciding to "eat healthy" works for some people: stopping soda pop, candy bars, cookies, desserts, beer, etc. That cuts a lot of fattening carbs right there.
Losing excess weight or controlling weight by avoiding carbohydrates was the conventional wisdom prior to 1960, as documented by Mr. Taubes. Low-carb diets for obesity date back almost 200 years. The author attributes many of his ideas to German internist Gustav von Bergmann (1908).
Taubes rejects the calories-in/calories-out theory of overweight that hasn’t done a very good job for us over the last 40 years. Taubes’s alternative ideas deserve serious consideration.
STRAIGHT UP, DOC . . . WHY AM I FAT?
Remember that insulin is the major fat-building hormone, and carbohydrates are the main cause of insulin release from the pancreas. Refined starches and concentrated sugars in particular raise insulin output. Overweight in advanced countries is usually caused by excessive consumption of these fattening carbohydrates.
A LOOK AHEAD
Recall that overweight results from an imbalance between energy intake and energy expenditure. You must overcome this imbalance if you are to lose weight.
By the time you finish this book, you'll have the facts and motivation you need to lose your excess weight and keep it under control for the long run. We'll briefly review physiology and nutrition, then explore the consequences of obesity and the benefits of exercise in more depth. Only then will you be ready for my eating plan for successful weight loss. Finally, I’ll tell you how to be successful at the most troublesome, frustrating, and mysterious area of weight control: long-term maintenance of weight loss.
KEY POINTS
66% of U.S. adults
are overweight or obese.
Fat is stored energy.
We have a
biological predisposition to store excess energy (calories) as fat.
Sedentary lifestyles and abundant food contribute to fat
storage.
Insulin is the primary fat-storage hormone.
Overweight
in advanced countries is usually caused by excessive consumption of
fattening carbohydrates such as refined starches and concentrated
sugars.
Gary Taubes' "carbohydrate/insulin theory of obesity"
is a major advancement in current thinking about the cause of
overweight.
Chapter 1: Why We Eat and What Happens Next
"Would you like fries with that?" the clerk asked Tom after he ordered a Big Mac, apple pie, and chocolate shake at the drive-thru. He was already salivating. "Sure, why not?" Tom didn’t realize, or care, that he had just ordered 1,770 calories, which is about what many people eat in an entire day. Tom eats three meals a day. It sure tasted good.
Tom grew up in a small Texas town. At age 17 he was 6-feet, 2-inches (188 cm) tall and large enough to help take his high school football team to the state championship playoff his junior and senior years. Football reigned supreme on Friday nights back in those days, not only for Tom, but the entire town. With weightlifting and football practice, Tom was exercising about three hours on most days and eating 5,000 to 6,000 calories. He didn’t call it exercise, it was just who he was. He remembers often washing down an apple pie with a quart of milk in one sitting. Yes, the whole pie.
Like his father, Tom was a meat-and-potatoes kind of guy who ignored most fruits and vegetables. That was rabbit food. His favorite meal was slow-cooked barbecue brisket, potato salad, and baked beans flavored with brown sugar and bacon. Tom’s wife, Barbara, knew that the men in his family were prone to overweight, heart attacks, high blood pressure, and high cholesterol. Tom stubbornly resisted her gentle pressure to eat healthier, whatever that meant. Eating was about enjoyment, in his mind, not about what his body needed.
Tom was a passable student and earned a football scholarship at a Texas college. A severe knee injury at the end of his sophomore season put the kibosh on his dreams of a pro football career and sidelined him for a good year while healing. He had always loved working with his hands, so he dropped out of college to become a full-time carpenter. His bosses at the construction company eventually rewarded his management skills by making him a supervisor. After that, he did less physical labor, but worked more hours. In his 30s, Tom still enjoyed the Friday night football games. But now he was sitting in the stands sipping sodas and chowing down on corndogs. He wasn’t exercising three hours a day anymore, but he could still finish off a whole pie in a day. His only exercise was an occasional trip to the park to play catch with his young son.
Tom’s father had his first heart attack at age 59, when Tom was 37. Dad had seemed the picture of health, except for the spare tire around his middle. Reality assaulted Tom with the fact that Dad might not always be around. Tom even thought about changing some of his own health habits. He heard all about the diet and lifestyle changes recommended by his father’s doctors. Barbara made sure of that! But Dad recovered and Tom put health concerns on the back burner.
Six months later, Tom started having chest pains right behind the breastbone. His first thought was, "Oh, no! Is this what a heart attack feels like?" He couldn’t have a heart attack at age 37, could he? Typical for a man, Tom ignored it as best he could. The first pains resolved spontaneously. The later pains seemed to improve with Maalox or Tylenol. But the pains got worse and more frequent. It was getting harder to hide it from Barbara.
During a particularly bad spell, he broke into a cold sweat as his heart palpitated. Realizing how bad off he was, he wondered if he would be around to see his son grow up. That’s when he admitted he better get some professional help and a life insurance policy. Calling 911 was definitely the right thing to do. He let Barbara make the call, then he was admitted to my service at the hospital.
Tom was lucky. Tests showed he was only suffering from an unusually bad case of heartburn; stomach acid was irritating his esophagus. We could manage that condition with medication and diet changes, but his eating habits were sending him a warning. I shared with him my sense that he was headed toward an early heart attack, like his father. His eat-whatever-tastes-good diet, high blood pressure (154/100 mm/Hg)), high cholesterol (250 mg/dl or 6.5 mmol/l), high triglycerides (310 mg/dl or 3.5 mmol/l), sedentary ways, and his weight all added up to an unhealthy lifestyle. His "game weight" at age 20 was 220 pounds (100kg), all muscle and bone. Now he was 308 pounds (140 kg), with much less muscle. Tom’s encounter with his own mortality accomplished what his wife’s health-conscious exhortations could not. He was now ready to make major lifestyle changes, and asked for my guidance.
PHYSIOLOGY, NUTRITION, AND WEIGHT LOSS
If you have absolutely no interest in science or how your body runs, skip the rest of this chapter.
To lose your excess fat safely and permanently, you must understand how you acquired it in the first place and how fat tissue fits in with other components of your body. We need to review some basic principles of physiology and nutrition.
Physiology is the branch of biology dealing with the functions and vital processes of organisms or their parts and organs. Nutrients are substances in food that are used in the body to provide energy and structural materials, and to regulate the growth, maintenance, and repair of the body’s tissues. Nutrition as a science is the study of nutrients in foods and of the body’s handling of them in processes necessary for life, growth, and optimal health.
The commercial success of worthless weight-loss scams is testament that many people are relatively ignorant of nutrition and physiology. Some have forgotten what they once learned. Others are subject to wishful thinking or delusion. Many want to believe that weight loss is easy, that a session with a hypnotist will do the trick, that a vitamin and herb mix will "melt away the fat," that weight-loss pills alone are a safe long-term solution, that they can eat anything they want if they are in the right program. But wishing does not make it so.
There are six major classes of substances (called nutrients) that the body uses for growth, maintenance, and repair of tissues. They are water, fat, protein, carbohydrates, vitamins, and minerals.
A healthy 140 pound (64 kg) body contains about 85 pounds (39 kg) of water and 25 pounds (11 kg) of fat. The remaining 30 pounds (14 kg) are mostly protein, carbohydrate, and the bone minerals: calcium and phosphorus. All other minerals and vitamins together weigh less than a pound (0.5 kg).
Your body can make some nutrients for itself. But there are at least 40 specific nutrients, each one essential for health, that you can obtain only from food. Eating the right foods is critical.
WATER
Without water, there is no life as we know it. The sum of chemical and physical processes necessary for the maintenance of life is called metabolism. Nearly all these processes occur in, or are dependent on, water. Life is a myriad of chemical reactions mostly occurring inside cells. Cells are the smallest living structural units capable of independent functioning. Millions of cells of different types are joined together to form our various tissues and organs. In addition to participating in many chemical reactions, water transports various vital materials (such as vitamins, minerals, sugar, amino acids) within and between cells. Water carries waste products away from cells.
A healthy body is 55-60% water. On average, we lose three to four cups (800 ml) of water per day through sweating and breathing (water vapor). Also, the kidneys must produce at minimum two cups (480 ml) of urine daily to carry away waste products. We must replace these obligatory water losses. Water balance is carefully regulated by interactions between the brain (hypothalamus, pituitary), kidneys, adrenal glands, mouth, and stomach.
Water is so important that we can only live a couple weeks without it.
FAT
For too long, dietary fat has been demonized as bad for us. In fact, it has many wonderful attributes as a component of our diets and bodies. As a nutrient, it provides us with fat-soluble vitamins (A, D, E, and K), enhances food flavor, and provides building blocks for cell structures (e.g., cell membranes) and hormones. Moreover, dietary fat is a great source of inexpensive energy. As part of our bodies, fat provides insulation to conserve heat, provides shock absorption and cushioning (e.g., the buttocks), and stores huge amounts of energy. In the sphere of human relations, sufficient fat in the right places is essential to physical attractiveness.
Terminology of Fats
"Fat" can refer to all three types of lipids: triglycerides, sterols, and phospholipids. But usually fat refers to triglycerides, which make up 99% of stored body fat.
Triglycerides are composed of carbon, oxygen, and hydrogen atoms arranged as a molecule of glycerol with three fatty acids attached. A fatty acid is a chain of carbon atoms with attached hydrogens and an acid group at one end.
Carbon atoms must have four bonds with adjacent atoms. A fatty acid carrying the maximum possible number of hydrogen atoms is "saturated." Red meat typically is high in saturated fatty acids. If a couple of adjacent hydrogen atoms are missing, the two side-by-side carbon atoms in the chain form a double bond.
A fatty acid with one double bond and two hydrogen atoms missing is a "monounsaturated fatty acid," such as oleic acid. Olive oil has lots of monounsaturated fatty acids such as oleic acid.
A fatty acid with two or more carbon double bonds (and four or more missing hydrogens) is "polyunsaturated," such as linolenic or linoleic acid. Most vegetable oils fit this description.
Vegetable and fish oils have an abundance of polyunsaturated fats. Olive and canola oils are rich in monounsaturates. The tropical oils are an exception. Despite plant origins, coconut and palm oils are primarily saturated.
Food manufacturers can synthesize fats by adding hydrogen to the carbon-to-carbon double bonds in liquid vegetable oils. Food labels often refer to these artificial fats as hydrogenated or partially hydrogenated vegetable oils, trans fats, or trans-fatty acids. "Trans" refers to the altered three-dimensional configuration of the new molecule.
A triglyceride is formed when the acid ends of three fatty acids attach to glycerol. Triglycerides usually contain mixtures of fatty acids with variable carbon chain lengths and degrees of saturation. Fats and oils are overwhelmingly (95 percent) triglycerides.
There are two fatty acids that we need but our bodies cannot make: linoleic and linolenic acid. Nutritionists call these "essential fatty acids" since we must eat them for optimal nutrition and, indeed, for life. We can make other fatty acids by combining two-carbon fragments derived from carbohydrates (e.g., sugar), protein, and alcohol. The new fatty acids attach to glycerol, forming triglycerides which can be taken up by fat cells. This is how excessive intake of non-fat nutrients, especially carbohydrates, leads to overweight.
In addition to triglycerides, there are two other types of lipids: sterols and phospholipids. Well-known sterols are cholesterol, vitamin D, sex hormones, bile acids, and cortisol. They share a basic structure of carbon, oxygen, and hydrogen arranged in multiple rings.
Sterols in food are a minor source of calories. Our bodies synthesize the sterols we need for metabolic processes. For example, the liver manufactures the cholesterol that becomes a major component of new cell walls. Over 90% of total body cholesterol is tied up in cell walls.
Phospholipids have a structure similar to triglyce-rides but contain a few atoms of phosphorus and nitrogen. They serve primarily as cell wall components.
Do Dietary Fats Cause Heart Disease?
Until just recently, physicians thought that dietary fat and saturated fats in particular were a major cause of atherosclerosis, also known as hardening of the arteries. The hardening isn't so bad; the problem is that it's accompanied by obstructive plaque in the walls of arteries. The plaque impairs the flow of blood to vital tissues, and the plaque can rupture, allowing the sudden formation of a blood clot that stops all blood flow. Tissue downstream from the clot dies. So atherosclerosis is the cause of most heart attacks, strokes, and poor circulation. It also contributes to high blood pressure.
The American Heart Association in 1957 recommended that polyunsaturated fats replace saturated fats in an effort to reduce heart and vascular disease. U.S. public health recommendations in 1977 were to reduce fat intake to 30% of total calories to lower the risk of coronary heart disease (atherosclerosis of the heart arteries). Slowly, some fats were replaced mostly with carbohydrates, highly refined ones at that. This shift tends to raise blood triglycerides and lower HDL cholesterol levels, which may themselves contribute to atherosclerosis. Current recommendations are, essentially, to keep saturated fatty acid consumption as low as possible.
The latest scientific evidence, however, indicates that total dietary fat and saturated fat have little, if anything, to do with causing atherosclerosis, heart attacks, strokes, or poor circulation in most people. (For details, see Selected References at the end of the book.) In fact, replacing dietary fats with carbohydrates may have contributed significantly to the steady rise in overweight and obesity we've seen over the last forty years in the U.S.
Trans fats, however, are still thought to contribute to heart and vascular disease. Food manufacturers using these man-made fats continue to reduce utilization in response to public pressure and concern. A safe minimal level of consumption has never been established.
Digestion and Utilization of Fats
After a meal, digestive juices inside the small intestine go to work on ingested fats (triglycerides), removing two or all three of the fatty acids from the glycerol molecule. The resulting pieces are absorbed by cells lining the small intestine, where they are re-assembled into triglycerides. These new triglycerides are extruded into the bloodstream and circulate all over the body to be used either as an immediate source of energy or stored in fat tissue as a future energy supply. Fat cells pluck any excess triglycerides from blood and store them as a glob of fat.
Later, when other cells need fuel energy, fat cells break down the triglycerides and kick fatty acids and glycerol into the bloodstream. The energy-starved cells pick up these triglyceride fragments and break them down further in chemical reactions that ultimately yield carbon dioxide, water, and energy.
Thanks to fat stores, a person of average weight can survive up to two months of total starvation. A fatter person can survive even longer.
PROTEIN
Proteins are complex chains of amino acids that play vital roles:
- in growth,
replacement, and repair of all tissues
- as enzymes regulating
chemical processes
- as antibodies fighting infection
- in
fluid balance
- in acid-base balance
- as hormones (e.g.,
insulin, thyroid hormone)
- in blood clotting
- as an emergency
energy source when carbohydrates and fats are limited.
Amino acids have a central carbon atom with four attachments: a hydrogen atom, an amino group, an acid group, and a variable side group or side chain. The 20 common amino acids are distinguished by their individual side groups.
Most proteins are composed of between 20 to several hundred amino acid building blocks linked together chain-like in a specific sequence. Chains of amino acids may also be linked together, often via sulfur atoms, to form even larger complex molecules. For instance, insulin consists of a specific sequence of 51 amino acids in two chains linked by sulfur bridges.
Food digestion breaks down dietary protein into its component amino acids, which we then use to make the proteins we need. If not available from the diet, our bodies can synthesize 11 of the 20 common amino acids.
But there are nine amino acids that we cannot make and must obtain from food. These are referred to as "essential amino acids." If not in the diet, the body will break down its own proteins to obtain these essential amino acids. Avoid this self-cannibalism by eating the right foods!
Formation of protein in a cell requires that all the needed amino acids be available simultaneously. Non-essential amino acids are pulled out of the circulating pool or manufactured right in the cell. But if the diet supplies too little of an essential amino acid, protein synthesis will be limited. Over time, the result is malnutrition.
A "complete protein" food contains all nine of the essential amino acids, in about the right proportions as humans require. Proteins in foods from animals - poultry, fish, meat, eggs, cheese, and milk - are generally complete. Eggs and milk contain particularly high-quality proteins.
Plant-derived foods provide less protein per unit of measure, and tend to be deficient in one or more essential amino acids. Soy protein, however, is complete and is sometimes used as a meat replacement. Vegetarians who exclude all animal-derived foods can receive all the amino acids they need if they eat a variety of legumes, grains, vegetables, nuts, and seeds (e.g., sunflower, sesame). The idea is to combine two or more foods so that the essential amino acids missing from one are supplied by the other.
For healthy adults, the protein Recommended Dietary Allowance is 0.8 grams per kilogram of appropriate body weight per day. This is about 50 grams for an average-sized person. As examples, a slice of bread has three grams of protein, a cup (240 ml) of milk has eight grams, a cup of beans has 13 grams, and three ounces (84 g) of meat has 21 grams of protein. We in the United States generally eat much more protein than needed.
CARBOHYDRATES
Carbohydrates mainly serve as a source of energy for us, providing about half of the energy in the standard American diet. The other half comes mostly from fat. Relatively little of our energy comes from protein.
There are essential amino acids (in proteins) and there are essential fatty acids (in fats): "essential" meaning our bodies cannot make them so we must eat them for life and health. There are no essential carbohydrates; we can make the ones we need.
Carbohydrates contain only carbon, oxygen, and hydrogen.
The most fundamental carbohydrate is a simple sugar called glucose. It's used as an energy source by all the cells in our body. It's like the gasoline needed to run a car, a car that's always running. Although we eat relatively little pure glucose, most dietary carbohydrates are converted during digestion to glucose, which is used as fuel. Any excess glucose not needed immediately for energy is converted to a storage form, called glycogen, for later use. We have the capacity to store only a half day’s worth of energy in glycogen. Carbohydrates are converted to fat when eaten in excess of what we can use immediately as energy or store as glycogen.
The preceding paragraph is exceedingly important for anyone with an excess weight problem. Read it again.
Carbohydrates are composed of sugars. Basic sugar molecules contain six carbon atoms, twelve hydrogen atoms, and six oxygen atoms. The various atoms are arranged in simple structures to form the three most basic sugars: glucose, fructose, and galactose. These ring-like structures are called monosaccharides.
When a chemical reaction joins a pair of monosaccharides together, the result is a disaccharide. The one most familiar to you is sucrose, or table sugar.
Sucrose, lactose, and maltose are the three most important disaccharides. Each of them has a glucose ring molecule attached to a ring of fructose, galactose, or another glucose. Lactose is the major carbohydrate in milk, contributing up to 50 percent of its calories. The monosaccharides and disaccharides are "simple carbohydrates," also called sugars.
"Complex carbohydrates" are much larger molecules composed of straight or branched chains of linked monosaccharides, mostly glucose. The three important complex carbohydrates, also known as polysaccharides, are starch, glycogen, and fiber.
Starch is a storage form of energy in plants. Through photosynthesis, green plants use sunlight’s energy to form carbohydrates from carbon dioxide and water. Carbohydrates not used as structural parts of the plant can be stored as glucose chains, i.e., starch. After planting, the starch in a grain of corn supplies energy to the seedling until it can capture sunlight’s energy through its leaves. Starchy foods such as wheat, rice, potatoes, and legumes provide not only energy but potentially a wealth of vitamins, minerals, and other healthful substances if they are not removed by processing.
Glycogen is a storage form of energy in animals. It's composed of numerous glucose molecules tied together in highly branched chains. In contrast, starch chains in plants are unbranched or only occasionally branched. Glycogen and starch are otherwise so similar that glycogen is sometimes referred to as animal starch. One third of total body glycogen is in the liver, two thirds is in muscle tissue. Muscle is stingy, tending to hold onto glycogen-glucose for its own use. On the other hand, a major function of the liver is to rapidly breakdown glycogen and release glucose into the bloodstream whenever another tissue needs energy.
Fibers are mostly complex carbohydrates forming the structural parts of plants. Cellulose is a good example since it's the primary structural element of all plant cell walls and you're familiar with it as a component of paper. Human digestive enzymes cannot break down the types of bonds between fiber monosaccharide units. Fiber passes undigested through the small intestine, but bacteria in the large intestine partially digest it. This benefits the bacteria and we get a few short-chain fatty acids in the bargain.
Eating too much dietary fiber can cause intestinal discomfort and gas, may interfere with absorption of some nutrients (e.g., minerals), and may be so filling that they displace other necessary nutrients that we might have eaten if not full. That’s not a big worry, though. Inadequate fiber intake is much more prevalent and may have adverse health consequences. The potential health benefits of high dietary fiber intake include:
- lower blood
cholesterol
- improved blood glucose levels in diabetics
-
improved weight control
- prevention of constipation, hemorrhoids,
and diverticulosis
DIGESTION AND UTILIZATION OF CARBOHYDRATES
When you eat a baked potato or bowl of rice, chewing stimulates the salivary glands to secrete an enzyme that starts breaking down complex carbohydrates into smaller polysaccharides. The small intestine does the bulk of digestive work; chemical reactions governed by enzymes disassemble starches and disaccharide sugars down to monosaccharide units (glucose, fructose, and galactose). Monosaccharides are absorbed into the blood and flow downstream to the liver, where fructose and galactose are converted to glucose.
At this point you have a hefty load of glucose in the liver and must "decide" what to do with it. There are only two choices: kick it back into the bloodstream for distribution to energy-hungry cells, or store it as energy to use later. If you're already overweight, you want to store it as glycogen instead of fat, or burn it up as an energy source right now.
One of the liver’s major functions is to store glucose (as glycogen) and release it as needed. Cells need a constant energy supply and can get that energy from glucose or fat. Some tissues, most notably the brain and nerves, are almost entirely dependent on glucose as their energy source. Cells take glucose out of circulation and split it into smaller fragments, yielding energy, carbon dioxide, and water.
Even when cells use fat for energy they still need some glucose for the most efficient utilization of fat.
Our bodies have elaborate mechanisms for maintaining blood glucose at an optimal range (about 70-140 milligrams per deciliter or 3.9-7.8 mmol/l) so that cells, particularly in the brain and nerves, don’t "run out of gas." Blood glucose falling too low triggers the breakdown of glycogen into glucose, which the liver pumps into the bloodstream.
Just how much glucose is circulating in our bloodstreams anyway? In a normal, healthy state, not much: about a teaspoon (5 ml).
While fat tissue stores enough energy to last for weeks, we can only store enough glycogen to last a matter of hours. When it is gone, the body can produce significant amounts of glucose only by disassembling proteins or fats.
Your body just isn’t able to convert much fat into glucose. Remember that fats are triglycerides: three fatty acid chains attached to a small glycerol molecule. You can convert the glycerol into glucose, but glycerol is only 5% of the fat molecule. The fatty acids can be broken down through a process called fatty acid oxidation, producing energy, but not glucose. Our bodies can also make limited amounts of glucose from dietary protein or by breaking down our own body proteins.
So the glucose your body craves as immediate fuel usually comes from daily dietary carbohydrates, or from the limited glycogen stored in your body.
What happens if you drastically reduce your consumption of carbohydrates for days on end? Where do your cells get the energy needed to survive and thrive? It gets most of it from your body fat stores, which break down to fatty acids and glycerol. The fatty acids are metabolized (oxidized) to supply energy to most tissues. Glycerol and proteins provide the glucose needed by the brain and nerves.
This switch in energy metabolism from one based on carbohydrates to one based on fats is how, for example, people can live for a couple months without any food whatsoever. It also explains how we sleep through a long night and skip occasional meals without adverse effects.
The idea that we need to eat carbohydrates every few hours to keep our energy up is a myth.
Insulin and Carbohydrate Handling
The digestion of a meal containing carbohydrates causes blood sugar (glucose) levels to rise. In response, the pancreas gland secretes insulin into the bloodstream to keep sugar levels from rising too high. The insulin drives the excess sugar out of the blood, into our tissues. Once inside the tissues’ cells, the glucose will be used as an immediate energy source or stored for later use. Excessive sugar is stored either as body fat or as glycogen in liver and muscle.
When we digest fats, we see very little direct effect on blood sugar levels. That’s because fat contains almost no carbohydrate. In fact, when fats are eaten with high-carbohydrate foods, it tends to slow the rise and peak in blood sugar you'd see if you had eaten the carbohydrates alone.
Ingested protein can and does raise blood sugar, usually to a mild degree. As proteins are digested, our bodies can make sugar (glucose) out of the breakdown products. The healthy pancreas releases some insulin to keep the blood sugar from going too high.
In contrast to fats and proteins, carbohydrates in food cause significant - often dramatic - rises in blood sugar. Our pancreas, in turn, secretes higher amounts of insulin to prevent excessive elevation of blood glucose. Carbohydrates are easily digested and converted into blood sugar. The exception is fiber, which is indigestible and passes through us unchanged.
During the course of a day, the pancreas of a healthy person produces an average of 40 to 60 units of insulin. Half of that insulin is secreted in response to meals, the other half is steady state or "basal" insulin. The exact amount of insulin depends quite heavily on the amount and timing of carbohydrates eaten. Dietary protein has much less influence. A pancreas in a healthy person eating a very-low-carbohydrate diet will release substantially less than 50 units of insulin a day.
To summarize thus far: dietary carbohydrates are the major source of blood sugar for most people eating "normally." Carbohydrates are, in turn, the main cause for insulin release by the pancreas, to keep blood sugar levels in a safe, healthy range.
You’ve learned that insulin’s main action is to lower blood sugar by transporting it into the cells of various tissues. But that’s not all insulin does. It also 1) impairs breakdown of glycogen into glucose, 2) stimulates glycogen formation, 3) inhibits formation of new glucose molecules by the body, 4) promotes storage of triglycerides in fat cells (i.e., lipogenesis, fat accumulation), 5) promotes formation of fatty acids (triglyceride building blocks) by the liver, 6) inhibits breakdown of stored triglycerides, and 7) supports body protein production.
Insulin actions No.4 and No.5 are particularly problematic if you're trying to get rid of excess body fat. To paraphrase: insulin promotes storage of body fat and impairs breakdown of existing fat tissue. Not good if you want to get rid of excess fat. In that instance, wouldn't it make sense to try to reduce insulin release by the pancreas? You do that by cutting down on easily digestible carbohydrates like sugar-sweetened drinks and refined flours and starches. Or reduce total carbohydrate consumption. Or both.
VITAMINS
I vividly recall a patient of mine, a known alcoholic, who was brought to the emergency room by his wife because he was unable to walk without help. He was fine until a few days earlier when he noticed spells of double vision. I found him also to be confused and cross-eyed. He wasn’t drunk. His prompt improvement after an infusion of a specific vitamin into his bloodstream confirmed my suspicion: he had a thiamine deficiency.
Vitamins are organic substances that are vitally necessary in small amounts for normal growth and activity of our bodies. All can be obtained naturally from food. We only need tiny amounts since they are not energy sources or tissue building blocks.
Thus far in nutritional science, 13 vitamins have been identified. They are divided into categories based on whether they dissolve in water or oil (fat).
The water-soluble vitamins are vitamin C, the B vitamins (thiamine (B1), riboflavin (B2), niacin (nicotinic acid), biotin, pantothenic acid, B6 (pyridoxine), folate (folic acid), and B12 (cobalamin).
The fat-soluble vitamins are A, D, E, and K.
Fat-soluble vitamins are stored in our fat tissue and are released to the other tissues as needed over weeks or months. Water-soluble vitamins generally cannot be stored; excess intake is flushed out quickly by the kidneys. The take-home point: we need to eat water-soluble vitamins almost every day.
Vitamin deficiency diseases are uncommon in the developed world, thanks to an abundance of various foods and food fortification with added vitamins (e.g., flour with folate, milk with vitamin D). In fact, disorders of vitamin overdose may be more common than deficiency. It’s a different story in parts of the Third World. Vitamin A deficiency, for example, is a major nutritional problem in the developing world, contributing to childhood blindness and premature death from infections.