Friday, November 19, 2010

The Nutrition Debate #2: Nutrition 101: A Primer on the Fundamentals of Nutrition

Food has three principal nutrients. They have been designated the Macronutrients. They are: Fat, Protein and Carbohydrate (hereinafter sometimes referred to as “carbs”). Essentially, all of the energy (measured in calories) derived from food comes from these three components.

Foods also have non-caloric nutrients, namely vitamins and minerals, called Micronutrients, as well as water and ash. In addition, foods have important but not yet well understood (or even discovered) Phytochemicals, such as antioxidants, whose benefits are believed vital, indeed essential, to our health and well being.

The energy content of either a gram of protein or a gram of carbohydrate is four (4) calories. The energy in a gram of fat is nine (9) calories, thus making it more than twice as “dense” in calories as either protein or carbs. A gram of ethyl alcohol (ethanol) in an alcoholic beverage contains seven (7) calories but alas no nutrient value.

The 97 calories in a 1 ½ ounce jigger of spirits (vodka, gin, scotch, etc.) are 100% ethyl alcohol. These are indeed “empty calories,” whereas the 119 calories in a 5 oz. glass of white wine are about 90% alcohol and 10% carbs (red wine: 122c./88%/12%). The 146 calories in a 12 ounce regular Budweiser are 67% alcohol, 29% carbs and 4% protein, while the 96 calories in a 12 ounce Michelob Ultra are 85% alcohol, 11% carbs and 3% protein. So, drink beer and wine -- for energy!

Most “sugar-free” candies and “energy bars” contain “sugar alcohol,” which does not elevate blood sugar levels (making them tempting to diabetics). They are, however, not carb-free or calorie-free!

The total available energy of a food is therefore the sum of the products of the weight (in grams) times the calories per gram of the macronutrients of which it is comprised. Fortunately, there are lots of software programs and books (including a USDA database: (www.nal.usda.gov/fnic/foodcomp/search/) that could do all this work for us, so no math is necessary to know how many grams or how many calories of each macronutrient, or the total potential energy (in calories), are contained in a portion of food. Suffice it for this primer to establish an understanding of this basic science.

To that end you should, I think, if you are interested in healthy eating and a long life, be interested to know the macronutrient distribution and balance of your diet. It was not so in the Paleolithic Era, referenced in the 1st installment of this tract. It was then just about survival. It should be noted, though, that it was by “survival of the fittest” and “natural selection” that we “learned” what we needed to eat to enable our survival and evolutionary development. Obviously, from the point of view of an individual’s survival, heuristic learning (by trial and ERROR) is a tough way to learn what to eat!

Half a century ago, in the U. S., some big-government advocates apparently thought so. That’s when politicians and public health officials got involved in establishing nutrition standards (and later, Dietary Guidelines) for Americans. The HHS/USDA is the purveyor of the current U. S. standard. It is represented by the “Nutrition Facts” panel that is required by them to be on all manufactured and processed food packages. It states: “Percent Daily Values are based on a 2,000 calorie diet.” Within the Nutrition Facts panel it also states the percentages for each Macronutrient that one “portion” of that food contains. In addition, it states the percentages for the various sub-classes of Fat (saturated, monounsaturated and polyunsaturated and trans fats) within Total Fat, and also the sugar and fiber (if any) within Carbohydrates. Further, the manufacturer is required to provide percentages for Cholesterol and Sodium, as well as for two (2) minerals and two (2) vitamins. Some manufacturers add percentages for other ingredients as well.

Of course, you cannot have a percentage of something without having a 100% value for it; therefore, it follows that the HHS/USDA has established that value and by extension the “standard” that has become known today as the “Standard American Diet” (unfortunately, SAD, for short). In the SAD, if you do the math, you will see that the minimum “percent daily value” (no longer “Recommended Daily Allowance”) for carbs is 300 grams (times 4 calories per gram = 1,200 calories, or a whopping 60% of a 2,000 calorie diet). The “daily value” for protein is 50g (x 4 = 200 calories or 10% of 2,000). And the “daily value” for fat is 65g (x 9 = 585 calories or +/- 30% of a 2,000 calorie diet. Add it up: 60%+10%+30% = 100% and 1,200 + 200 + 585 calories = 1,985, rounded to 2,000 calories. Note that there is no government “percent daily value” for sugar on the panel, whereas there is a standard for saturated fat. Hmmm…

This means that our government currently recommends that Americans eat a diet comprised of 60% carbohydrates (all of which break down to sugars in the blood, i. e. glucose), with unlimited sugars within that 60%, all this while enjoining us to avoid eating fats, especially saturated fats. Simultaneously, during the same 40 to 50 years, most of us have become fatter, and many of us are becoming (or have become) Type II diabetics (like me). There is, or if not, ought to be, therefore, a raging debate on the subject of nutrition, as we see the increasingly obese population all around us, and hear about the emerging “diabetes epidemic.” I will have more to say on this debate in the next and future installments, but first, I want to say a word to exculpate the average beleaguered physician with a clinical practice.

For over 50 years (longer than the entire time that virtually any doctor still in practice has been in practice), the prevailing wisdom passed down from the powers-that-be has wavered but little. The sources of information that the medical practitioner has relied on are, writ large, our public health officials and, in particular, the practitioner’s medical community, through their specialty practice standards, medical journals and conventions, and the ubiquitous pharmaceutical salesperson. For the most part, practicing physicians were not trained much (if at all) in nutrition, except for basic biochemistry; they have had little time to “bone up” on an area that isn’t being pushed by big pharma. And, finally, the nutrition field, especially the basic science with which the clinical practitioner has less interest and exposure, has advanced very dramatically in the last twenty years. So, I do not blame them. I sympathize with (most of) them. They are stuck in the status quo of the mainstream message and, like the government, are “committed” and unable to turn around, or even waver, in the face of compelling and mounting evidence.

This suggests to me that it may be time for the patient to assume responsibility and take charge of his (or her) own health, from a dietary point of view. In the next installment, I will tell you how I think we got to be in this place. It’s an interesting story.

Thursday, November 18, 2010

The Nutrition Debate #1: A Very Brief (and Necessarily Select) History of Numan Nutrition (and Dieting)

In the beginning, there were the hunters and the gatherers. This was, in the History of Nutrition, the Paleolithic Era, and hence we have the derivative Paleo Diet. In most cultures, men hunted and women and children gathered foodstuffs as they were available to them. Early humans adapted to periods of feasting and starvation (fed and fasting states, in dieting terms). We will return to this in later installments of this multi-part series.

We humans were then of necessity omnivorous. It was a survival thing. We are supposed to have eaten (or otherwise used) every part of the animals we were lucky or skilled enough to trap or club or impale with lance or shoot with bow and arrow or spear (fishes). Every part of the animal (or fish) including the organ meats (offal), the blood, and even the marrow from within the cavity of the bone, was eaten. Some of us still enjoy these foods today.

We also ate all the things we could gather from fruit trees and vines, and the leaves and roots and fungi that didn’t kill us. It was a trial and error thing, but we learned that to survive we had to take risks (both in hunting and gathering) and make the most of what was available and safe to eat. I have often thought that this is why children have a natural aversion or “distaste” for “new” foods and only gradually increase the scope of what they will eat as they mature. Remember when you wouldn’t eat (blank) – fill in the blank? For me, it was brussel sprouts, which today I love, especially tossed in olive oil and roasted.

Then, as we became more “civilized” and gathered together for protection and socialization, we wandered about less and began to settle. This development came about and was undoubtedly enabled by the beginnings of agriculture. We saw that grains, that is, the seed heads of certain grasses (cereal grains such as corn, wheat, and rice) grew naturally where nature planted them. Why wander about when we could plant our food supply, we reasoned, and cultivate and water and harvest it where we lived? This also enabled us to build more permanent shelters and live in fertile places with good fresh water supplies and abundant game and other animal life. We also learned that we could catch (instead of kill) certain animals and domesticate them for a steady food supply as they multiplied naturally in captivity. Wundebar! Surely, this was a milestone, indeed a hallmark, of human evolution.

Could life get any better? Perhaps. But, in the view of increasing numbers of today’s students of these developments, this was also the beginning of mankind’s downfall, nutritionally speaking. It was the dawn of the onset of the age that was to bring us the dreaded Diseases of Civilization. It was the advent of the Neolithic Age, and it began about 10,000 years ago.

Fast forward to about 150 years ago. William Banting¹, a retired London undertaker, wrote and published (in 1863) a 16-page pamphlet titled Letter on Corpulence – Addressed to the Public. In it, the 5 foot 5 inch, 200 pound Banting, surely a fat man, described a program of eating in which he “scrupulously avoided eating any…food that might contain either sugar or starch.” On Banting’s diet, he ate 5 or 6 ounces of meat or fish at each of three meals every day, together with a fair amount of wine and spirits, but avoided altogether “bread, milk, beer, sweets and potatoes.” Banting dropped about 50 pounds in 18 months. His pamphlet became a sensational best seller in England and on the Continent, and launched the now infamous Very-Low-Carb Diet (definition of VLC to follow).

William Banting credited his diet to William Harvey, an aural surgeon in London who had recently “been to Paris where he had heard the great physiologist Claude Bernard debate on diabetes.” In later editions of his astonishingly popular pamphlet Banting also credited two other Frenchmen, Jean Anthelme Brillat-Savarin and Jean-Fran├žois Dancel, whom The Lancet and the British Medical Journal said had earlier espoused similar views to Banting’s advisor, Dr. Harvey. Banting apologized for not giving the Frenchmen credit and simply explained he was not familiar with them.

Now, fast forward again to about 50 years ago (skipping the impact of the Industrial Revolution, including improvements in agricultural production through mechanization, and the movement of large segments of the growing population from rural areas to cities to work in factories, as well as various wars and conflagrations).

On January 13, 1961, Ancel Keys, a widely-respected University of Minnesota physiologist (after whom the K-Rations of WWII were named), made the cover of Time Magazine. Since the 1930’s Keys had been interested in the influence of diet on health. His work on the etiology and specifically the epidemiology of heart disease would later be published in a seminal tract, the Seven Countries Study (Harvard University Press, 1980), from which his hypothesis associating cholesterol and saturated dietary fat with heart disease was promulgated and asserted by Keys as the Lipid Hypothesis; hence, the Low-Fat Diet.

Keys’s Lipid Hypothesis will be the subject of the third installment of this series. But first, the second installment, which will be upcoming, will be a primer for non-scientists (and physicians) on “The Basics of Nutrition: Macronutrients, Vitamins, Minerals and Phytochemicals.”

¹ In this and the following paragraph the quotes and references are from the “Prologue: A Brief History of Banting” from Gary Taubes’ Good Calories – Bad Calories, 2007, Alfred A. Knopf. I especially recommend the 2nd (paperback) Edition for the Afterwords wherein Taubes discusses the response to his book by the medical community and why most doctors still don’t “get it.”

Archive of Columns Written by Dan Brown for The Millbrook Independent, Millbrook, NY

I've started this blog to create an archive of articles I have written for The Millbrook Independent, a weekly newspaper published in Millbrook, N. Y. The first installment appeared in print in the edition of Wednesday, November 11, 2010. I will post subsequent articles as they appear in print.

As this is my first "blog", as I explore its capabilities I may expand the blog to include a dialogue with readers.