Monday, January 31, 2011

The Nutrition Debate #7: Are you a “Sugar Burner” or a “Fat Burner”?

A restricted-calorie, balanced diet we have learned is a “starvation diet.” They don’t work because your body tells you that you are starving. You feel weak and tired and hungry, and your metabolism slows down. Your body is screaming for more “energy in” and eventually overrules your will power. The result: you shovel more energy in! The problem, of course, is that you are not letting your body get the energy it needs from the body fat you have stored for this purpose.

This would be a good time to go back and re-read Gary Taubes’s 10 “certain conclusions” in installment #4 in this series. If you didn’t save it, I have begun a Blog on Google’s Blogger site to post installments in this series after they are published. The URL is A Google search using the URL in the Internet Explorer (IE) search engine works. I understand that a search in the Firefox browser or the Google Chrome search engine will also bring it up. When you find it, pay special attention to conclusions 2, 8, 9 and 10.

Now, let’s get back to The Nutrition Debate. The food we eat, when digested, is rapidly absorbed -- sugars and starches more rapidly than fats and proteins. Sugars and starches are all carbohydrates and all become sugar (glucose) in the blood stream when they are completely broken down by the digestive process. The sugars and starches which break down most rapidly are said to have a high glycemic index, a term now familiar to us all.

The body prefers to use sugar and starches for energy because most of them are quick and easy to break down and burn. Fat takes a little longer, and has less precedence, as it was designed to be stored for times of famine. Protein takes the longest, remaining in the stomach for several hours. The good thing about fat, though, and protein too to a lesser extent, is that it provides a feeling of fullness (satiety). Carbs give us a quick “spike” of energy, but are then followed by a similarly precipitous “crash” and then that “hungry feeling” one gets (on a high carb diet) between meals.

This “craving” is the result of a hormonal signal calling for more glucose (more sugars and starches) to supply more quick energy (in the form of glucose) to the blood stream. It’s not signaling for protein or fat. It wants sugary foods and carbs that quickly become sugar (glucose) in the bloodstream. Some starch, like white bread, actually digest more quickly (have a higher glycemic index) than table sugar (sucrose)!

When you eat a diet that is largely comprised of carbohydrates, such as the Standard American Diet (SAD) which is 60% carbohydrate (see installment #2), you are, in metabolic slang, a “sugar burner.” You may eat healthy proteins and fats too, but your body is running on glucose and storing fat. It calls for you to eat more carbs whenever your blood sugar crashes, which is just a couple of hours after you last ate carbs. Because you are primarily burning carbs for energy, most of the fats you eat, plus extra carbs, and any excess protein (to be explained shortly), will be stored. The fats (and ultimately the extra carbs) will become triglyceride molecules and will be deposited within the fat cells of your adipose tissue. The protein, which breaks down to amino acids, will be taken up by the muscles and other body tissue to repair and restore them within 4 to 5 hours after it is eaten. Beyond that, they can’t be utilized by the body so they are sent to the liver where they are stored. Later, when there is a low blood sugar signal, the liver will reconstitute these amino acids (from the excess protein) as glucose, through a process of gluconeogenesis. And, as we know, the body uses glucose as its preferred source of energy, after stored carbs and before stored fat.

So, how do you get away from this endless cycle of “sugar” (glucose) spikes and crashes that characterize the SAD? How do we get away from this diet that is making us fatter, and sicker? And, if you need to lose weight, how do you become a “fat burner?” I think you know by now where I am going with this, but in the next installment I will first tell you something of the consequences of the dietary program our leaders have advocated and we have now been mainstreaming for the last fifty years. It is the story of one of the Diseases of Civilization, first described as Syndrome X and now more commonly known as the Metabolic Syndrome.

© Dan Brown 1/16/11

Saturday, January 29, 2011

The Nutrition Debate #6: “Energy In = Energy Out”: An Alternative Interpretation

The one universally held truth in our understanding of human metabolism is the Energy Equation: Energy In = Energy Out. It is accepted by most doctors, even some medical researchers, and universally by the popular press and the entire general public. Why? Because it is so easy to understand, and it’s just plain good “common sense.”

It also gains gravitas by its association with one of the basic laws of science, the First Law of Thermodynamics, paraphrased here just a bit: “the net (energy) supplied to the system equals the net work done by the system.” Who can argue with that? You’d have to be some kooky doctor or maverick scientist to even try, and you would be laughed at all the way to (and in) the grave (viz: Atkins).

Okay. I’m crazy enough to try. I get the courage because Gary Taubes, in his seminal opus “Good Calories – Bad Calories” introduced in the last installment, makes the argument convincingly for me. So, with apologies to him for any errors in my understanding, I will attempt to regurgitate his explanation here to help convey his Alternative Interpretation of this immutable law of thermodynamics, as applied to the Energy In = Energy Out formulation for weight control.

The problem with the conventional interpretation of the Energy In = Energy Out formula is that it measures “energy in” and “energy out” in the wrong place, i. e., exclusively outside the body, as something done to the body. Thus, the common-sense, universally accepted understanding is as follows: Energy In (food ingested) = Energy Out (basal metabolism plus the added energy expenditure of activities, including exercise). Therefore, to lose weight (“improve” the energy balance) you must restrict calories (i.e., reduce “energy in”) and exercise more (increase energy expended, i.e., “energy out”). Sound familiar? Of course! It’s the ubiquitous “diet and exercise” prescription. This interpretation of how the Energy Equation works, that is, where to measure “energy in” and “energy out,” is fundamentally wrong. Here’s why.

According to Taubes, the operative place to observe and measure homeostasis (how the body itself modifies energy intake and expenditure to maintain a balanced state), is in the blood stream. There, “Energy In” is the sum of the products of digestion and absorption (of nutrients from foods eaten), plus “quick” energy from food previously eaten, digested and stored (primarily as glycogen in the liver and muscles), and lipolysis, the breakdown and then oxidation (burning) of the body’s own fat cells. Thus, the source of our energy in the blood stream (the “energy in” or left side of the equation) is basically three-fold: 1) the small intestine (where digested food is absorbed into the blood stream), 2) stored carbohydrate energy (glycogen) available to the blood stream from the liver and muscles, and 3) our adipose tissue (fat cells, or triglyceride molecules), which, if allowed to break down, can move into the blood stream and contribute to “energy in.” Particularly take note of this last additional source on the “energy in” side of the equation, and the very important conditional aspect of it.

Thus, the body balances the equation itself, through complex signals from various hormones, putting on the right side of the equation however much energy it needs for our basal metabolism plus what our activity level requires. It uses the first two sources on the left side of the equation (food eaten and carbs stored), and then, providing it is “free” to take it, energy from the third source: it uses our fat cells for energy. This last energy source, however, is conditional and absolutely critical. This source of “energy in” is the critical difference that 1) avoids the starvation diet aspect of conventional restricted calorie but balanced diet programs, 2) prevents that always hungry feeling, including cravings and the need for between meal snacks, 3) gives the body all the energy it needs, avoiding that drained, and weak feeling that people get from balanced, starvation diets. It is also an easy way to lose weight (body fat) and keep it off, if you stay with it, for life.

When understood from this perspective, and with some additional insights from our knowledge of the macronutrient components of the foods we eat, and the key role of the hormone insulin, we can gain an understanding of how to use all three sources on the “Energy In” side of the equation to meet our body’s total requirements for “Energy Out.” In the next installment we’ll discuss what “free to use it” means, and how the mechanism works.

© Dan Brown 1/9/11

Friday, January 28, 2011

The Nutrition Debate #5: Gary Taubes and the Alternative Hypothesis

Gary Taubes first came to my attention as a result of the New York Times Sunday Magazine cover story of July 7, 2002, entitled, “What If It’s All A Big Fat Lie?” Taubes has won the Science in Society Award of the National Association of Science Writers three times, but his 2002 article was the first widely read refutation, for a popular readership, of the “high dietary fat/cholesterol/heart disease” (lipid) hypothesis. It also posited his “alternative hypothesis,” which is predicated on a very low carb way of eating. I didn’t know it at the time, but my doctor, an internist/cardiologist, had read the article and tried such a diet himself to lose weight. He succeeded and recommended that I try low carb eating too, also to lose weight. As an afterthought, he said, “By the way, it will probably help your Type 2 diabetes.” Boy, was he ever right about that!

Following the publication of his 2002 NYT article, Taubes was besieged to write a book detailing his findings and touting the “alternative hypothesis.” He refused and instead spent the next five years researching and writing “Good Calories – Bad Calories” (Alfred A. Knopf, 2007). He refused to produce a book for the popular readership because he said he did not want to produce a polemic. He wanted instead to research and present a history and analysis of all that has transpired in the field of obesity research and “science” – a word he uses sparingly and advisedly. This book is a very dense read, but getting through it is well worth the slog. In the end, in the Epilogue (pages 453-454), he proffers 10 “certain conclusions,” which I present in full below.

“As I emerge from the research, though, certain conclusions seem inescapable to me, based on the existing knowledge:

1. Dietary fat, whether saturated or not, is not the cause of obesity, heart disease, or any other chronic disease of civilization.
2. The problem is the carbohydrates in the diet, their effect on insulin secretion, and thus the hormonal regulation of homeostasis – the entire harmonic ensemble of the human body. The more easily digestible and refined the carbohydrates, the greater the effect on our health, weight, and well-being.
3. Sugars – sucrose and high-fructose corn syrup specifically – are particularly harmful, probably because the combination of fructose and glucose simultaneously elevates insulin levels while overloading the liver with carbohydrates.
4. Through their direct effect on insulin and blood sugar, refined carbohydrates, starches, and sugars are the dietary cause of coronary heart disease and diabetes. They are the most likely dietary causes of cancer, Alzheimer’s disease, and the other chronic disease of civilization.
5. Obesity is a disorder of excess fat accumulation, not overeating and not sedentary behavior.
6. Consuming excess calories does not cause us to grow fatter, any more than it causes a child to grow taller. Expending more energy than we consume does not lead to long-term weight loss; it leads to hunger.
7. Fattening and obesity are caused by an imbalance – a disequilibrium – in the hormonal regulation of adipose tissue and fat metabolism. Fat synthesis and storage exceed the mobilization of fat from the adipose tissue and its subsequent oxidation. We become leaner when the hormonal regulation of the fat tissue reverses the balance.
8. Insulin is the primary regulator of fat storage. When insulin levels are elevated – either chronically or after a meal – we accumulate fat in our fat tissue. When insulin levels fall, we release fat from our fat tissue and use it for fuel.
9. By stimulating insulin secretion, carbohydrates make us fat and ultimately cause obesity. The fewer carbohydrates we consume, the leaner we will be.
10. By driving fat accumulation, carbohydrates also increase hunger and decrease the amount of energy we expend in metabolism and physical activity.”

I’ve read “Good Calories – Bad Calories” twice, and re-read Taubes’s “certain conclusions” at least a dozen times. I am convinced that he’s got it right. But, after failing to get the reception he had hoped for in the medical community, Taubes finally relented and agreed to write a book that would be a little more accessible to the general public. Gary Taubes’s “Why We Get Fat: And What to Do About It” was published by Alfred Knopf last week (December 28, 2010). I’ve pre-ordered a bunch. Hardcover: $24.95. Amazon (hardcover): $13.41.The Kindle (Amazon) eBook edition is $9.99.

Next installment: The “Energy In – Energy Out” theorem: an alternate interpretation.

© Dan Brown 1/2/11