This week in Part IIIA of my series on food (I had to split Part III into two as the length was getting a bit out of hand), I’ll be discussing the challenges of maintaining a healthy diet in our current food culture in the U.S. If you want to start at the beginning, here are links to Part I and Part II. Parts IIIA and IIIB draw heavily from Michael Pollan’s excellent book “In Defense of Food: An Eater’s Manifesto,” which, in my opinion, should be required reading in our high schools.
Before proceeding, let me try to convey the critical nature of this topic. The food system in the U.S. has been moving in the wrong direction over the last several decades and the cumulative damage is both serious and undeniable. At the top of the page is a graph of rates of diabetes in the U.S. since 1958(1). This data includes both type I diabetes, which is genetic, for which rates have not risen, and type II diabetes, which is diet related and represents at least 95% of the 700% increase since 1960!
In Part II: The Science of the Stomach, I explained that your primary goal in selecting your food is to provide your body with the raw materials it needs to carry out all its necessary metabolic processes, as well as to construct all of the thousands of different molecules required by your body to make everything from bones to eye balls to nerve cells to, well, everything. Operating and maintaining you is a spectacularly complex operation. Consuming the necessary foods required for optimum performance, while always a challenging task, is now, rather ironically in this modern age, increasingly difficult. To my point of view there are four key reasons why this is the case. I’ll cover two this week and two next week in Part IIIB.
- We Don’t Really Know What all of the Needed Raw Materials Are
Nutrition science has taught us a lot about what foods are needed for healthy living. We know that we need amino acids, fats, cholesterol, minerals and vitamins. We are often able to identify the cause and effect when one of these items is missing. For example, lack of vitamin A in one’s diet can result in blindness. However, there are still many gaps in our nutritional knowledge base.
Just as our bodies produce a broad array of different molecules, so do the plants and animals that we consume. The dietary impacts of only a small handful of these molecules have been studied. For example, when we eat broccoli we have a fairly good understanding of how the vitamin C and iron improve our health, but little if any understanding of the specific benefits or detriments of other molecules, including numerous phytochemicals and cartenoids. We know that some of them are important, we just not quite sure which ones.
An example that Michael Pollan uses to illustrate this point that I found particularly compelling was the story of the first baby formula. In the late 1800s, Dr. Justin von Liebig discovered that the primary nutrients needed by plants where nitrogen, phosphorous, and potassium – these are noted on your fertilizer bag by their atomic symbols, N, P, and K – and came to the erroneous conclusion that plants needed only these three. He then applied this same flawed theory to people and made the world’s first baby formula from cow’s milk, wheat flour, and potassium bicarbonate. This concoction had plenty of nitrogen, phosphorus, and potassium, but it was a disaster for the babies it was fed to, as it was bereft of most everything they needed. They suffered a host of troubles, some deadly, the symptoms of which were lumped under the penumbra of “failure to thrive.”
If this sounds like a something that could only happen in the 19th century, I would suggest you pause, tone down the smugness, and understand that every time you see orange juice fortified with extra vitamin C or high-protein pasta, we are all still Dr. von Liebig’s test subjects. Just like Dr. von Liebig, we are still seeking the “magic bullet” in our diets, the single or small handful of “nutrients”, think, fish oil, antioxidants, red wine, the Mediterranean Diet, probiotics, and such, that will ride in on a white stallion and save us from our other questionable eating and health habits. As I’ll explore in part IIIB, this mistake stems from the misguided perception, fueled by billions of dollars of marketing and unscientific government policy, that at the dinner table we are eating nutrients rather than foods.
- Processing Food Removes Much of the Good Stuff
Recall that your task when eating is to provide the cells in your body with all the raw materials needed for life. Unfortunately, the predominate methods of processing food in the U.S. remove many of these raw materials leaving those who eat mainly processed foods with a number of nutritional deficiencies. The primary ways that processing food degrades their valuable raw materials are the precooking vegetables and the milling of grains.
The vegetable story is easy to explain and understand. A vegetable is at its optimum value as a food at the moment of harvest. (Not counting items harvested early on purpose to allow them to survive the lengthy trip to your local grocery store.) With time, temperature, and dehydration, many of the useful molecules in a vegetable decompose, reducing its usefulness as a food. For example, let’s say you go to the Harris Teeter and purchase a box of Rice-a-Roni Broccoli au Gratin(2) and feel sort of good about the purchase because of the broccoli. Unfortunately, when you serve it at the dinner table, the green specks in it may be modestly pleasing to the eye, but, from a chemical composition standpoint, they can no longer really be considered broccoli and no nutritional benefits remain.
The milling of grains is a more interesting and pernicious story. For brevity (such as I am capable of), I’ll focus on wheat, but bear in mind that the analogs for corn and rice are nearly the same. When harvested, wheat has three parts; in the middle is the endosperm, which is covered by the germ, which is further covered by the bran.
From the time humans began harvesting wheat until the Industrial Revolution, wheat was ground with stone, first by hand and later by water-wheel or wind-driven mills. Stone grinding removes the bran, a helpful step if one wishes to make bread, but leaves the wheat germ. Among the many useful food molecules in the germ, are oils, which, with time and air exposure, turn rancid and smelly. Therefore, stone-ground wheat needs to be eaten relatively soon after milling which, in turn, required that most towns had a nearby mill to supply flour.
The invention of roller mills in the 1800s made of iron, steel, or porcelain, allowed for the removal of the germ along with the bran, leaving on only the endosperm, paving the way for Wonder Bread, with the advent of white flour. This invention should get more attention in history books. White flour had two chief “advantages”; it was pure white, which was utilized as a marketing tool, and without the oil to spoil or other nutrients from the germ to attract insects, it had a long shelf life allowing for both high-volume storage and long-distance transport. The invention of the roller mill is ground zero for the devolving of our local food network, since it led to the construction of large, far-away mills built next to railroads which drove the local mills out of business. You could consider them the Wal-Marts of the 19th century.
White flour was a disaster for the poor of the Industrial Revolution, for whom bread represented a large portion of the calories they consumed. The removal of the wheat germ immediately resulted in nutritional deficiency diseases. Of particular trouble were, pellagra and beriberi, two devastating vitamin B deficiency diseases. By the 1930s, the worse of the deficiency diseases related to white bread were understood and the process of “fortifying” the bread by adding back items like vitamin B relieved some of the more well-known problems.
Consider though, that “fortifying” the white bread restores only a tiny fraction of the molecules that were in the now-removed wheat germ and, therefore, addressed only the most acute and easily recognized nutritional deficiencies. This analogy holds true for most of our processed foods; we remove a vast number of potentially useful nutrients and add back a handful that can then be touted on the package.
What we are now learning is that the steady conversion in the U.S. diet from whole to processed foods since the 1960’s is driving large increases in a number of chronic diseases. We have conclusive evidence that this trend is driving rates of obesity and diabetes. I suspect that in coming years we will learn that as our diets have begun to be as limited in nutrients as Dr. von Liebig’s baby formula, other diseases who’s incidence has been increasing of late are also diet related. There are several possible candidates that come to mind for me, but listing them would be pure speculation.
I’ll leave you with this thought for the week. Here, in this age of plenty, pediatricians across the U.S. are starting to note an increase in cases of a vitamin D deficiency disease you may not have come across since reading your last John Steinbeck novel, rickets. If you have a moment, Google “rickets in children.” You’ll get a hodge-podge of concern and conspiracy theory peppered with some scientifically questionable commentary on sunscreen use and breastfeeding. Fueling this conversation is the just-under-the-surface, right-beyond-the-corner-of-our-eyes, burgeoning concern that something has gone terribly wrong. It has.
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- Data from the U.S. Centers for Disease Control.
- Just for fun here is the ingredient list for Rice-a-Roni Broccoli au Gratin.
RICE, WHEAT FLOUR, PARTIALLY HYDROGENATED PALM OIL**, CHEDDAR, PARMESAN AND ROMANO CHEESES (MILK, CHEESE CULTURES, SALT, ENZYMES), SALT, REDUCED LACTOSE WHEY, WHEY, BROCCOLI*, ONIONS*, CORN SYRUP*, PALM OIL, NATURAL FLAVOR, CORN STARCH-MODIFIED, MONOSODIUM GLUTAMATE, CREAM, SUGAR, NONFAT MILK, SODIUM CASEINATE, ENZYME MODIFIED CHEDDAR CHEESE (MILK, CHEESE CULTURES, SALT, ENZYMES, SORBIC ACID), LACTIC ACID, SPINACH*, AUTOLYZED YEAST EXTRACT*, ANNATTO EXTRACT COLOR, CITRIC ACID, SOY SAUCE (SOYBEAN, WHEAT, SALT), NIACIN, SOY LECITHIN, FERROUS SULFATE, FERRIC ORTHOPHOSPHATE, THIAMIN MONONITRATE, FOLIC ACID, RIBOFLAVIN.
**ADDS A DIETARILY INSIGNIFICANT AMOUNT OF TRANS FAT
CONTAINS WHEAT, SOY AND MILK INGREDIENTS.