INTRODUCTION:

THE DISMAL TRUTH ABOUT DIETS


You may have heard a surprising statistic—it’s often said that about 95 percent of those who lose a significant amount of weight regain most of it. Or they may even go on to gain more weight, and they end up heavier than when they’d started. While there is some debate as to whether this statistic is accurate or not, we do know that the weight-loss industry in the United States was worth $66 billion in 2017. If diets worked long term, we wouldn’t keep throwing so much money at the problem, would we? (I have some good news for you here—intermittent fasting is free, it requires no supplements, and it might even save you money in the long run, since you won’t be eating as frequently.)

Why is it so hard to lose weight and keep it off? It’s because of our hormones and metabolic processes. Anyone who has had this struggle has felt the way our bodies seem to fight against us over time, leaving us heavier and worse off metabolically than we were before. The good news is that it isn’t your fault, and it isn’t because you are weak or can’t control yourself. It’s biology.

Let’s take some time to go down what I like to call the memory lane of dieting. Or you could call it Diet Crazy-Town. I think most of us have been there, either as a visitor or a permanent resident.

When I first jumped on the diet roller coaster, it was the 1980s and calories were king. It didn’t matter what you ate, just how many calories you consumed. I carried around my pocket-sized calorie counter and my little notebook and recorded every morsel that crossed my lips. Because I was young, I was always able to lose weight as long as I kept to 1,200 calories or fewer per day. Eventually, this strategy stopped working for me, and you will understand why as you continue to read this chapter. Even though it seemed to work for me at the time, it was no fun at all to put that much thought into what I was eating (Did I eat three chips, or four?), so I would get to my goal weight and then abandon calorie counting completely until my weight rebounded back up, and out came the notebook once again. What a vicious cycle to be trapped in!

Next up: the low-fat era! It was the 1990s, and fat was the villain. I read my first diet book, The T-Factor Diet, and it all made so much sense! America agreed; this decade marked the proliferation of fat-free products. Breakfast could consist of a fat-free muffin washed down with a Coke (because Coke is fat-free!). I remember making my favorite sandwich of the time: fat-free bologna on fat-free bread, spread with fat-free mayo and fat-free mustard. Sometimes I would have a whole sleeve of those fat-free marshmallow cookies covered in fat-free chocolate. Remember how fat-free cheese wouldn’t really melt, but instead looked like a square of orange plastic? Good times. (Funny story: I found a used copy of The T-Factor Diet recently and reread it. It’s actually all about choosing real foods that happen to be lower in fat, such as vegetables, whole grains, fruits, and lean meats. Nowhere in the plan did the author recommend that you buy Franken-products as fat substitutes. Oops. Somehow, we all missed that part.) I did lose weight as long as I kept my fat grams below a certain threshold, but when I look at photos of myself from that era, I looked very thin and yet completely unhealthy. Of course I did; I don’t think I was actually eating any real food in my quest to find fat-free food-like products.

After that, America turned against carbs. The low-fat crowd had it all wrong, and it was carbs we should be avoiding. During that phase, Dr. Atkins was my guru, as well as the Hellers, who determined that we were all “carbohydrate addicts” and told us what to do in The Carbohydrate Addict’s Diet. Once again, I started counting, and I ate as much as I wanted of the allowed low-carb foods. I never did lose any weight on a low-carb plan (which I now understand after having my DNA analyzed: according to my genetic profile, I am more likely to lose weight with a higher-carb/lower-fat approach. More about that in another chapter!). Everywhere we turned, there were low-carb versions of our favorite foods and plenty of Franken-food carb substitutes.

Of course, those are just a few of the diets I tried. In addition to the big diet trends of the decades, I jumped on every bandwagon that came along: I ate right for my blood type; I counted bites as if I had gone through weight-loss surgery (yes, this is a real diet plan, and yes, I can take really big bites); I ordered tasteless, expensive, and unappealing food through the mail; I tried hypnosis; I ate “clean”; I ate “dirty”; I used costly meal replacement shakes (and even tried to sell them to my friends to support my habit); I sweated to the oldies; and more. I even went through some physician-assisted programs that included both prescription diet pills and hormone injections that tricked my body into thinking I was pregnant so I could tap into my stored fat. (I am almost embarrassed to admit the last two, but I want to keep it real … plus, this shows you how desperate I was. Can you relate?) Yes, those all worked temporarily, but each of them left me with more rebound weight gain than the time before. Eventually, I yo-yoed myself up to 210 pounds, which is in the obese category for my five-foot-five frame.

When I look at all the things I tried over the years, I realize that I not only lived in Diet Crazy-Town, I could have been the mayor.

Fast-forward to the present. I am maintaining a weight loss of over eighty pounds, and I haven’t struggled to maintain the loss. Every year when the seasons change, I pull out my clothes from last year and try them on. I hold my breath … do they still fit?

And year after year, the answer is yes! Other than a few items that are now too big, my clothes continue to fit me season after season. I am effortlessly maintaining my weight without dieting, thanks to intermittent fasting and the magic of the clean fast, coupled with something called appetite correction, which you will learn about in another chapter. Instead of shopping in the plus-size department, I now fit into a size 0 or 2, and frequently I find my clothes in the petite section of the store. As the years go by and I enter my fifties (and go through menopause, with no resulting weight gain of any sort), I become more and more confident that my now-steady weight illustrates I have ended my weight struggle forever. #ThankYouIntermittentFasting

When you read my diet history, it may remind you of your own similar struggle. Yes, I am a real person, just like you. For decades, I tried and tried, and then I tried some more. If sheer effort made you thin, it would have solved the problem much earlier. If you are someone like me, you can relate to the struggle of continuing to get heavier and heavier over time, despite frantically following all the dietary advice that comes our way.

Take a deep breath.

It’s time for you to realize the number one most important concept of this whole chapter: YOU DID NOT FAIL DIETS. DIETS FAILED YOU.

Let that sink in.

IT IS NOT YOUR FAULT. It’s biology.

So? Why do diets like these leave us heavier and heavier over time? Why can’t we succeed, even though we are trying and trying?

Heck, I would like to let you know the sad truth: the harder you try, the harder it actually gets. Again, this is biology, and not personal weakness or failure. In a 2013 scientific review, it was reported that in fifteen out of the twenty studies they examined, past dieting was a predictor of future weight gain.1 That’s not a surprise to all the weary dieters of the world, is it? We diet. We regain the weight. We diet again. We regain the weight again. Is it because we are gluttons? No. (Even though the “naturally skinny” people may think that’s true. I remember back when I was struggling so hard for all the years before IF that I wanted to throttle my slim husband when he told me, “Just eat less food. Exercise more.” Gee, thanks, honey. Sigh.)

No, it’s not as simple as “Just eat less food. Exercise more.” There are many things that go on behind the scenes in the bodies of chronic dieters that explain the phenomenon of weight gain after dieting. Let’s look at the science to see why this happens.

To put it into simple terms, our bodies want us to survive and reproduce. And because of that, we have protective mechanisms that are in place to keep us from dying if our bodies perceive we are in a starvation crisis of some sort. This kept our ancestors alive during wars, droughts, and hard winters. Our bodies don’t understand that we are trying to slim down for summer bathing suit season, and instead, they think we are in terrible danger.

We have a great deal of scientific research that explains how this happens in the body. Some of the earliest research on this phenomenon began in 1944. As World War II came to an end, a scientist named Ancel Keys wanted to take a close look at how the human body responded to extreme deprivation and the subsequent reintroduction of food. He and his colleagues from the University of Minnesota conducted a famous study now known as the Minnesota Starvation Experiment.2 The topic was of immense interest because they knew that war-torn Europe faced the huge task of refeeding a population who had undergone a period of extreme deprivation due to the war. Prior to this experiment, little was known about the physiological and psychological effects of starvation. So, the purpose of this study was to gain insight into the physical and emotional effects of semistarvation and to see what would happen when food once again became available.

Keys and his colleagues gathered thirty-six volunteers. These were young men known as conscientious objectors, who rejected the notion of fighting in the war but still wanted to make a meaningful contribution in a nonviolent way. For the researchers to gather baseline data, the men first went through a three-month period where they received approximately 3,200 calories of food per day, which was designed to keep their weight stable. Then they went through a six-month period where they were fed a “starvation diet” that included the foods available to the population in Europe after the war, such as potatoes and other root vegetables, brown bread, and macaroni. During the final three months, the subjects went through a “nutritional rehabilitation period” where they were randomly assigned to four different groups for a variety of refeeding methods so the researchers could determine how their bodies responded to the reintroduction of food.

During the starvation period, the expectation was for the men to lose about 2.5 pounds per week, so their food intake was decreased according to how well they were progressing toward their goals. If their weight loss slowed, the amount they were given to eat was decreased so that they would continue losing weight at the required pace. They were also expected to walk twenty-two miles per week. This certainly sounds like modern-day eat less / move more advice, am I right? If you’ve ever counted calories as a part of a diet plan, I am sure you remember that you had to eat less and less over time just to keep seeing weight loss, and that is just what happened here with these men.

During this starvation period, the men lost enthusiasm for their low-calorie diet as time passed. They reported having less energy, increased irritability, a decreased tolerance of the cold, and a lack of concentration. They became preoccupied with food and developed routines such as playing with their food and chewing and eating very slowly to make their meals last longer. Several of the men began collecting cookbooks and recipes, and they would spend their spare time fantasizing about food. Physically, their metabolic rates slowed over time as their calorie intake went down. They didn’t just lose fat; they also lost valuable muscle mass.

Notice that Keys used the word starvation to refer to this period of the experiment. Every time I read about this study, it is surprising to realize that the men were fed an average of 1,800 calories of food per day during the period that was the “starvation” period. If you are a long-term dieter like me, you may look at that number—1,800—and think, WHAT?!?!?! Seriously, 1,800 calories per day was considered starvation level?!?!?! I remember my own low-calorie dieting days, and my calorie target was always to eat 1,200 or fewer calories per day—1,800 seems like a feast compared to the restrictive 1,200 I’d allowed myself. That goes to show that when we follow extreme low-calorie diet plans, we are usually subjecting ourselves to even more restriction than the participants in the most extreme “starvation” experiment in history were following.

After the starvation phase, the three-month refeeding period began. We can learn important lessons from this refeeding phase. The men continued to feel tired and weak for quite some time, and they also continued to feel extreme hunger, which for many didn’t even end after they were released from the experiment to go back to their regular lives. You see, their bodies responded to the starvation period by ramping up their hunger hormones, which increased their drive to eat. This is one of the protective measures our bodies have in place to encourage us to get in the amount of food our bodies think we need to recover from the terrible tragedy we must be experiencing. One participant had to have his stomach pumped due to binge eating. Another got sick after eating in a restaurant because he simply “couldn’t” stop eating. Sound familiar? Have you ever restricted calories for a while and then felt like you couldn’t stop bingeing afterward? Now you know that it wasn’t because you were weak; it was your body’s biological drive sending you “EAT NOW!” signals. It wasn’t your fault at all.

Interestingly, when the amount the subjects could eat was restricted during the refeeding phase, their resting metabolic rates stayed low—having dropped during the starvation phase—and remained low due to the continued restriction. However, when they could eat as much as they wanted, their metabolic rates rapidly recovered. This illustrates that we have hope when it comes to reversing the negative metabolic adaptations that come along with low-calorie dieting. Continued restriction over time leads to a continued decrease in metabolic rate, but eating a sufficient amount of food can actually increase your metabolic rate over time. That is very good news for any of us who may worry that we have permanently damaged our metabolisms from years of dieting—it is possible to recover!

We learned a lot from the Minnesota Starvation Experiment, but let’s fast-forward to the modern era. In 2016, a group of scientists came together to examine what happened when people lost a great deal of weight quickly in a famous study that is usually referred to as the Biggest Loser Study.3 The official title of the study was Persistent metabolic adaptation 6 years after The Biggest Loser competition, and just from the title, you can see that the changes continued six years after they had competed on the show. In the study, they discovered a continuing “metabolic adaptation,” meaning that the participants had a lower resting metabolic rate (RMR) than would be predicted based upon their new body sizes and ages alone. This study resulted in sensational headlines upon its release, and the tone of the articles indicated that losing weight and keeping it off was apparently a hopeless endeavor.

You see, in this study, the participants’ RMRs were calculated before they started, again at the end of the thirty-week competition, and again six years later. Overall, fourteen of the contestants participated in the follow-up study. The scientists used all the data on hand to calculate what the participants’ RMRs should have been (based on their new sizes and ages), and when they compared the expected RMRs to their actual RMRs, they discovered that even though their RMRs were as expected at the beginning of the process (before weight loss), their average RMRs (six years later) were approximately five hundred calories lower per day than would be expected based on their new body sizes and ages. Not only did their metabolic rates slow, but they remained slower than expected over time. Also, the participants who lost the most weight had the greatest slowing of their metabolic rates, and those who successfully maintained more of the weight loss had an even greater metabolic slowing than those who did not maintain their loss. The researchers were actually surprised to see that the metabolic adaptation increased over the six-year period for these participants.

So, why did the most successful participants experience the greatest metabolic slowdown over time? We can look back at the Minnesota Starvation Experiment data for a clue. If you remember from the Minnesota Experiment, those who were not permitted to eat according to appetite in the refeeding phase (meaning they continued to restrict their eating over time) had metabolic rates that stayed low. Applying that to The Biggest Loser participants, those who managed to keep the weight off by sheer determination (and continued dieting) found that their metabolic rates continued to get slower and slower over time. Yep. This illustrates the very real truth: the harder you try to keep your calories low, the lower and lower you have to go to maintain the weight loss. While it can be done, it is a difficult (and often demoralizing) way to live your life.

Have there been other studies that also report this metabolic adaptation after a period of weight loss? Yes. In fact, multiple studies support this phenomenon.4

So, why does this happen?

In 2017, a group of scientists reviewed the large body of available research and found that weight loss results in an “energy gap” that leads to higher ghrelin levels (ghrelin is the hunger hormone), a larger than expected decrease in leptin (leptin is the satiety hormone), a higher than predicted decrease in resting metabolic rate, a higher than expected decrease in the thermic effect of food, and larger than predicted adaptive energy-saving behaviors. This is precisely what we saw in the Biggest Loser Study.5

All of that was a mouthful of scientific jargon. Let’s break it down. What does this mean, in layman’s terms?

Basically, when you lose weight, your body responds by:

Increasing ghrelin, your hunger hormone. This means that you have an increased drive to eat. It’s why you find yourself arm-deep in a bag of potato chips and you just can’t seem to stop eating. Your hunger hormones are driving this behavior, not your conscious brain.Decreasing leptin, your satiety, or satisfaction, hormone. This means that you eat and eat but don’t feel satisfied. It’s why you keep eating until your stomach hurts—you aren’t getting the “you’ve had enough” signal that would tell you to stop eating.Lowering your metabolic rate and decreasing the amount of energy that you use daily. And this can be as much as 25 percent below what would be predicted based on your smaller body size. This is a protective measure; never forget that your body loves you and wants you to survive! It’s why you find that your energy wanes and you just don’t have the drive to get off the couch to go to the gym.Hunger goes up. Satiety/satisfaction goes down. Metabolic rate / energy expenditure decreases. All of this works in tandem to cause the weight regain that is so common for dieters.6

Think about this from your experience with diets. Now you understand what went on: the longer you dieted, the harder it was to stick to the diet, and it’s because your body ramped up ghrelin to send you “EAT NOW!” messages. Once we understand this, we can recognize that a stronger urge over time to “EAT NOW!” is an absolute red flag that your body is in distress, and it isn’t a sign that you are “weak” or “failing.” It’s a sign that your body is functioning exactly as it is supposed to, in fact. So, breathe a big sigh of relief and know that we can trust the signals our bodies are sending us. More about that in the chapter about appetite correction. (Spoiler alert: it’s absolutely amazing how fasting “fixes” our appetite signals!)

Again, please understand that all of this illustrates that it is not your fault when you “fail” at a diet. Your body is adjusting your hormone levels and metabolic processes to save your life. Your body doesn’t know that you are trying to fit into a smaller size of clothes or look better on the beach. All your body knows is that you appear to be in some sort of danger, and drastic measures need to be taken behind the scenes so you will survive. #SayThankYouToYourBody

I know that hearing about the high failure rate of diets and the metabolic adaptations and hormonal changes that occur in our bodies when we lose weight can make us want to throw up our hands and give up before we even start. Yes, it’s true that to burn stored fat and lose weight, we need to eat less food than our bodies require. And it’s also true that our bodies have many protective mechanisms in place that lead to rebound weight gain after a period of restriction.

The big question is: How do we eat less food and keep from slowing our metabolic rates? Can we prevent this dreaded adaptation and the corresponding hormonal changes that result in rebound weight gain and a damaged metabolism?

Good news! Intermittent fasting initiates positive hormonal and metabolic changes in our bodies that make it very different from the low-calorie diets we have done before. So, even though you may be eating less food while living an intermittent fasting lifestyle, fasting protects your body from the more detrimental effects of metabolic adaptation. (And some people even find that they can eat more food than they were eating before starting IF and still lose weight, thanks to these positive hormonal and metabolic changes.) Even better, your hunger and satiety hormones get back into balance, allowing you to finally feel satisfied after eating. Hunger doesn’t go up and up; it actually goes down over time. Keep reading to learn how this happens!


Copyright © 2020 by Gin Stephens