By Fred Pescatore, MD, MPH
Everywhere we look, we see something about low-carbohydrate dieting—television, radio, bookstores, and newspapers. Everyone we know seems to be on a low-carbohydrate diet. But what is low-carbohydrate dieting and how do we know which diet to follow, which is the healthiest, and most important, does it really work? In this brief article I am going to show you exactly what low-carbohydrate diets are and compare and contrast the most popular ones currently available with a diet I have been working with for the past few years.
I used to be the associate medical director of the Atkins Center for Complementary Medicine. Yes, that is the same Dr. Atkins whose very popular diet plan has swept the nation. In the five years I worked there, I was able to learn, first-hand, the health benefits of low-carbohydrate eating, but I was also able to learn which aspects were healthy and which ones were just hype.
When I first started working there, I had just finished residency training and knew nothing about nutrition. After all, they didn't teach nutrition in medical school, nor was it emphasized when you were working in a hospital trying to handle life and death emergencies. Nutrition was something that was always left up to the dieticians. The doctor had to order the diet, but none of us really knew what the diets we ordered ever consisted of. Looking back, I now know what a terrible mistake this was.
In a nutshell, low-carbohydrate dieting consists of eliminating most forms of carbohydrates. Carbohydrates come in many forms. They can be sugars, breads, pastas, pretzels, crackers, fruit, vegetables, and soda and fruit juices. Many people can't believe that fruit and fruit juices are carbohydrates because they are really mostly sugar. Several recent studies even go so far as to suggest that the rise in obesity in our population is directly attributable to the rise in the consumption of fruit juices.
For those of you who may not be aware of how fattening fruit juices can be, apple juice has more sugar in it than the same amount of soda. Sugar is the food that is eaten the most in this country. We eat 150 pounds per person, per year. That translates to 33 tablespoons each day. That may seem like an unrealistic amount, but when you begin to understand what you are eating, it is really quite easy to get to that level quickly without even realizing it. When I place my patients on the diet program I use in my practice, they come back in two weeks into the program, after having read all the food labels, and tell me that they can't believe certain foods actually contain sugar. What's worse, there are more than 300 foods that are not required by the federal government to list sugar as an ingredient, when in fact, they do contain sugar. As Americans, we consume more calories of sugar than we do of meat, chicken, vegetables, and breads combined.
Different forms of sugar
One of the main reasons we don't know how much sugar we consume is because sugar has many disguises, such as brown sugar, corn syrup, honey, molasses, maple syrup, high-fructose corn syrup, dextrin, raw sugar, fructose, polyols, dextrose, hydrogenated starch, galactose, glucose, sorbitol, fruit juice concentrate, lactose , brown rice syrup, xylitol, sucrose, mannitol, sorghum, maltose, and turbinado. Essentially, any word on a food label that ends in -ose, or -ol is a sugar in disguise.
Why is keeping a low carbohydrate level so important? The explanation requires a little understanding of the basics of how food is metabolized in the body. Our bodies metabolize food in the same manner as the bodies of our prehistoric ancestors. The body preferentially uses sugar for fuel since the body doesn't have to expend any energy to break it down for fuel. Next, the body will utilize simple carbohydrates such as pasta, bread, pretzels, and the like, simply because it doesn't take much energy to convert these into sugar for fuel. Next, the body uses complex carbohydrates such as vegetables, brown rice, legumes, and whole-grain starches as fuel because the body has to expend energy to process these foods back into sugar in order to be used by the body. The body will then use protein for fuel, and use fat last.
The reason the body uses fat last is because fat is the perfect storage molecule for the body. Fat holds more than twice the amount of energy than either a carbohydrate or a protein, so the body, in its infinite greatness, will store those bits of energy (also known as calories) for a rainy day. For most of us in this country, that rainy day never comes and it is our hips and waist that suffer the brunt of this storage of energy.
The next logical assumption should be to eliminate fat from the diet and by doing so would solve the fat problem—right? Wrong! Because our bodies create stores of fat molecules, namely triglycerides, we have an excess of sugar in our bodies. The real key to dieting is therefore to eliminate the bottom of the food chain—sugar and simple carbohydrates—thus, forcing our bodies to utilize the complex carbohydrates, protein, and fat that we consume. Our bodies then begin to operate as they were meant to operate. Our prehistoric forefathers never had processed foods, and that is all sugar and simple carbohydrates are.
By eliminating sugar and simple carbohydrates, we can lose weight easily and efficiently. I explained this concept to a patient I will refer to as Susan. She was 43 years old and was a strict believer in the low-fat philosophy, yet no matter how strict she was, she gained weight, felt less energetic each day, and needed to lose about 60 pounds. In order to explain the concept of how food is metabolized, I often measure blood insulin levels. Her insulin level was twice the normal amount when she was fasting and more than four times the normal amount two hours after she had eaten.
High insulin levels have been linked to a variety of diseases: Diabetes, blocked coronary arteries, high cholesterol, high triglyceride levels, high blood pressure, strokes, and most important, obesity.
Insulin is the hormone in your body that reduces your blood sugar. When there is too much blood sugar, in a condition known as insulin resistance, your body becomes overwhelmed and can't do its job. A high-carbohydrate, low-fat diet can never correct this insulin imbalance or any underlying cause of obesity because it is too high in sugar. When you eat a low-carbohydrate, high-protein diet, your body can better metabolize the food that you eat and the insulin levels return to normal, and the weight comes off. Even if you are not overweight, the proper regulation of insulin levels is the key to avoiding some of the deadliest diseases that we face in this country.
Safe and Healthy Eating
I keep emphasizing low carbohydrate rather than no carbohydrate because that is the real key to dieting in this way in a safe and healthy fashion. Bill, a 54-year-old executive came into my office about 40 pounds overweight. He had tried all of the more popular low-carbohydrate diets and had lost about 50 pounds, but he suddenly got stuck, and for the past six months, was unable to get the scale to budge, despite having increased his sessions with his personal trainer.
I explained to him my theory as to why the body needs some good carbohydrates—in order to get the metabolism to function efficiently. I also explained to him that when the body is placed into ketosis, for example, for an extended period of time, that gimmick stops to work. Ketosis is actually what happens to your body when it is starving and your body begins to break down muscle protein. Your body will adapt and the ketosis becomes less effective at helping the body to lose weight. You can only fool Mother Nature for so long. I gave him the program I use, which consisted of more carbohydrates than he had been consuming for over a year, and within three months, he lost the remaining 40 pounds and an extra 10 to "play around with," as he put it. He was able to do this because he had learned which carbohydrates to eat, and was not told, "eat all you want."
Moderation is the Key
Many of the low-carbohydrate diets that are currently popular encourage the notion of "all you can eat." While this certainly works in Las Vegas, it can't possibly be expected to work over the course of someone's lifetime. You simply can't tell an overweight person to eat all of anything. It is the wrong message to send out.
The message to eat all the fat you want without worrying about it is also wrong. The most important thing I learned while at the Atkins Center was that the amount of fat does play a role in how much weight a person will lose. Also, the type of fat is vitally important. There are good and bad fats available for us to consume. I just don't buy the belief that eating all the bacon fat you want is healthy for you.
The medical literature supports the theory of "good" and "bad" good fats such as omega-3 fatty acids—the type you find in fish. The medical literature similarly supports the theory that there are fats you shouldn't be consuming, like the trans fats found in margarine and the hydrogenated fats found in most oils, except for olive oil and canola oil. The current fad-diet books do not take any of this research into account when helping you devise an eating plan that is supposed to make you healthy and stay that way.
Another popular book tells you that you should eat a meal that consists of anything you want as long as you do it in a certain time frame and that it is a certain set number of meals. For example, every third meal, you are allowed to eat all you can eat for an hour. That is a gimmick if you ask me. As you cannot tell an overweight person to eat all of anything, you cannot tell an overweight person they can eat any kind of food and still lose weight healthily. In medical school, I went on a chocolate pudding and French-fry diet and managed to lose weight, but it was not a healthy way to do so. Many people want to lose weight. More than half of us are seriously overweight. If you want to do something about it, you need to learn how to eat a proper diet.
The Thin Mind
Thin people think and treat food differently than we do. We need to learn how to eat and think like they do if we want to have any hope for success in the long run. And isn't that what it's all about—a lifetime of good health and looking good?
I should know, as I was once 80 pounds heavier than I am today. For the first time in my life, I can actually say that I have been thinner for longer than I was ever overweight. It is because I have been able to incorporate a sensible low-carbohydrate diet into my life.
Don't be afraid of low-carbohydrate dieting—it is healthy and it does work. Be afraid of gimmick diets. They may just be snake oil after all.
(c) 2001 Healthology, Inc.