5

Reductionism Invades Nutrition

The first problem for all of us, men and women, is not to learn but to unlearn.

—GLORIA STEINEM

Now that we understand the fundamental flaws of the reductionist paradigm in general, it’s time to explore how this paradigm has distorted and degraded nutrition and human health.

I know food and nutrition aren’t considered to be very important outside my little world. The newspapers I read have sections on politics, business, sports, and entertainment, but none of them devotes a daily section to food policy. Food writers are restaurant critics or purveyors of recipes, relegated to the same pages of the newspaper devoted to hairstyles, fashion, and home decor. But food is pretty much the most important topic there is. No food, no civilization. Crop failures, outbreaks of mad cow disease, and contaminated produce could bring our society to its knees very quickly. We assume we’re immune to such catastrophes because most of us think about food as the stuff we buy at the supermarket. And every time we go to the supermarket, guess what? It’s overflowing with food. We aren’t going hungry, so everything must be fine.

But just because we don’t think about our food all the time doesn’t mean it’s not critically important. Most of us don’t obsess over our oxygen supply, but people who find themselves submerged in water or trapped in a smoky building can think of nothing else. Food is as fundamental to our survival as oxygen. But while we all breathe the same air, we have lots of choices when it comes to food, and those choices determine not just how we eat, but also how we utilize our agricultural land, what our government subsidizes, what we teach our children, and what sort of society we create.

In the same supermarket, we can choose to fill our carts from the produce section, the dairy case, the meat freezer, the canned goods aisle, or the packaged-goods aisle. We can get our produce from local growers or from giant factory farms in South America. We can eat out at fast-food restaurants or cook in our own kitchens. And when our choices cause us to gain unacceptable amounts of weight, we can adopt any one of a thousand different diet plans, from Atkins to Paleo to Weight Watchers to macrobiotic. All these individual choices add up to affect our national food “system,” just as the food system itself strongly influences those individual choices. Both the system and our personal choices have been heavily driven by our beliefs about nutrition.

If they weren’t, would such a large percentage of food packaging be taken up by nutritional labels? Why else would the federal government spend so much money and time creating food groups, food pyramids, recommended daily allowances, and daily minimum requirements? Why else would the FDA create and enforce rules about what food, drug, and supplement manufacturers are allowed to claim as health benefits?

So although it doesn’t make the news very often, food, and our national policies about it, determine a great deal about our society. And nearly everything our society believes about nutrition has reductionist fingerprints all over it. In this chapter, we’ll explore how the reductionist paradigm has led to poor nutritional policy and confused consumers, as well as how and why nutrition resists the reductionist model our society works hard to put it in.

REDUCTIONIST NUTRITIONAL SCIENCE

The definition of the word nutrition is something I’ve thought about a lot: every so often during my fifty years in academia, our nutrition faculty would have a retreat and spend some of the time trying to figure out what the word really means. These could not have been very productive, because the same discussion had a way of reappearing at every retreat.

Each time, we’d eventually conclude with some default definition, something resembling the ones found in standard dictionaries. Something like “a process of providing or obtaining food necessary for health and growth” (Oxford English Dictionary) or “the act or process of nourishing or being nourished; specifically the sum of the processes by which an animal or plant takes in and utilizes food substances” (Webster’s).

I don’t like either definition. Webster’s definition fails partly on technical grounds because it uses the word nourished, which is a derivative of the word nutrition. You can’t define a word by referring to itself! That Webster’s resorts to this sleight of hand shows how troublesome the word really is.

The other, more substantial problem with the Webster’s entry is the word sum. I remember sums from grade school math. We added two numbers and got a third. The third, which we called the sum, was nothing more or less than what you got by adding the first two numbers. That’s the very soul of reductionism, remember: the sum (total) can be completely known if you know each individual part.

Both Oxford and Webster’s use the word process, which points to something important but, on its own, is inexcusably vague. The Oxford definition focuses entirely on the process of nutrition as something that occurs outside the body: food is either provided or obtained. This leaves no room for nutrition as an internal, biological process, nor a complex one. To reductionists, nutrition is just the arithmetic summation of the effects of individual nutrients. These misleading definitions in two of the most respected and frequently used English dictionaries show how profoundly the reductionist concept is embedded in our culture.

If you were taught statements like, “Calcium grows strong bones,” “Vitamin A is necessary for good eyesight,” and “Vitamin E is a cancer-fighting antioxidant,” you learned nutrition the same way. The same is true if you count calories, or pay attention to percentages on the nutritional labels on packaged foods, or wonder if you get enough protein, or start slathering your fries in catsup because you hear tomatoes are a good source of lycopene.

These beliefs make sense only in a reductionist paradigm that identifies the component parts of food—the individual nutrients—and figures out exactly what each one does in the body and how much of it we need. And this is precisely what we scientists are trained to do. I was taught nutrition in this way and I taught it the same way to my students. This included an upper-level course in biochemistry at Virginia Tech, an upper-level course in nutritional biochemistry at Cornell, and two new graduate-level courses in biochemical toxicology and molecular toxicology for a new graduate field of toxicology, also at Cornell. Like other faculty in these fields, I followed the typical textbook model of lecturing, mostly focusing on individual nutrients, individual toxic chemicals, individual mechanisms of action (i.e., biochemical explanations), and individual effects, as if there were, for each nutrient or chemical, one main mechanism that explains and perhaps controls the relationship between cause and effect.

When I taught nutrition in this traditional, reductionist way, here’s how it went. We began by considering the chemical structure of the nutrient. Then we discussed how it functions in the body: its absorption across the intestinal wall into the blood; its transport through the body; its storage; its excretion; and the amounts needed for good health. We talked about each nutrient on its own, as if it acted alone in a totally mechanical fashion. In other words, teaching nutrition meant getting students to memorize facts and figures and chemical pathways to pass tests without asking them to think about the context for these discrete bits of information.

We do the same thing in research as we do in education. The gold standard of nutritional research—the type that receives preference for funding and gets published in top-line journals—focuses on one nutrient and one explanation of its effect. My experimental research program focused on the effects of discrete causes, reactions, enzymes, and effects, oftentimes outside of the context of the body as a whole—in part because, as I mentioned, I, too, was taught to think this way,¹ but also because, in order to get research funding, we scientists are forced to focus our hypotheses and experimental objectives on outcomes that can be measured.

Let me give you a specific example from the initial stages of my own research on cancer formation initiated by aflatoxin (AF), a chemical known to cause liver cancer. (As you may recall from the introduction, AF was the carcinogen produced by the peanut fungus I was looking at in the Philippines.) Figure 5-1 summarizes the process we were studying (using a diet of 20 percent casein, or milk protein).

My lab research at this early stage was completely acceptable according to the reductionist rules. We focused on one kind of carcinogen (AF) that caused one kind of cancer (hepatocellular liver cancer) that depended on one kind of enzyme (mixed-function oxidase) that metabolized AF to produce one kind of highly reactive product (AF epoxide) that produced one biochemical effect (the very tight chemical bonding of the epoxide to DNA that causes genetic damage), each stage of which seemed internally consistent and biologically plausible. And we discovered that the more the carcinogen bound itself to the DNA, the greater the amount of cancer occurred.² Aha! This was the mechanism that “explained” the effect of protein on cancer!

FIGURE 5-1. A linear model of cancer causation from aflatoxin

A couple of thoughts about the previous paragraph: first, I don’t expect you to understand everything I wrote. I’m describing complex biological and chemical reactions in the kind of specialized language used by scientists everywhere to communicate with precision. All you need to know is that, according to this model, A causes B, which causes C, which leads to D. So the more A (cancer-causing chemical) you start with, the more D (cancer) you end up with.

Second, it probably sounds pretty convincing, even if you don’t really understand it. Research like this seems airtight because it deals with objective facts—reactions, genetic mutations, and carcinogenesis—as opposed to messy things like human behavior and lifestyle. Only by excluding messy and complex reality can we make linear, causal statements about biological chain reactions.

Although we worked diligently on this series of studies for many years, obtained very impressive results, and published lots of professional papers, we were still left with a major unanswered question: did this finding—that higher dietary casein intake produced more cancer in rats—tell us anything about other proteins, chemical carcinogens, cancers, diseases, and species (e.g., humans)?

In other words, did this startling outlier result about dietary protein suggest that our love affair with animal protein was misguided and dangerous? Did cow’s milk in modest quantities promote cancer in humans? What about other diseases? Did other animal proteins have the same effect? While I tried for decades to answer these questions using reductionist tools, it gradually dawned on me that these questions often strayed beyond what reductionist science could answer. Not because you couldn’t set up experiments to compare the effects of a diet high in animal protein with other factors typically found in a WFPB diet. Those have been done, and the results are jaw-dropping (particularly the research and clinical experiences of Esselstyn, McDougall, Goldhamer, Barnard, and Ornish, some of which we touch on elsewhere in this book).

No, the problem with reductionist research is that it’s too easy to run experiments that show what appears to be just the opposite effect: that milk prevents cancer. That fish oil protects the brain. That lots of animal protein and fat stabilizes blood sugar and prevents obesity and diabetes. Because when you’re looking through a microscope, either literally or metaphorically, you can’t see the big picture. All you can see is a tiny bit of the far larger truth, completely out of context. And whoever has the loudest megaphone—in this case, the ones shouting that milk and meat are necessary for optimal human health, whose megaphones are thoughtfully provided by the meat and dairy industries—has the most influence.

I’m sure that given enough time and money, I could conduct reductionist-style experiments that show health benefits for Coke, deep-fried Snickers bars (these are very popular at the North Carolina State Fair), and even AF (we actually showed such effects once in our lab³). I’d have to manipulate the sample (say, studying the effects of Coke on people dying of thirst in the Sahara, or the effects of a Snickers bar on the mortality rate of tired drivers at 2 A.M.). I could also measure hundreds of different biomarkers and report only on the outcomes that support my bias. Or, like the elephant examiners we met in chapter four, I could perform honest research and still end up with conclusions that are incomplete and misleading because of the limited scope of my vision.

This is why we so frequently see conflicting research results in the media: the predominant research framework actually encourages such conflicts. This same reductionist framework is also why our society’s beliefs about nutrition often seem so contradictory and confusing, whether we get them from textbooks, food packaging, or government messaging.

REDUCTIONIST NUTRITION IN THE SUPERMARKET AND THE HOME

Though reductionism originates in the lab, it pervades the public imagination as much as it does the thinking of academics. Because we scientists and researchers are considered “experts,” our worldview permeates our culture’s understanding of nutrition at every level.

Pick up an elementary or high school nutrition textbook and you will inevitably find a list of known nutrients. There are about a dozen vitamins and minerals, perhaps as many as twenty to twenty-two amino acids, and three macronutrients (fat, carbohydrate, and protein). These chemicals and their effects are treated as the essence of nutrition: just get enough (but not too much) of each kind and you’re fine. It’s been that way for a long time. We’re brought up thinking of food in terms of the individual elements that we need. We eat carrots for vitamin A and oranges for vitamin C, and drink milk for calcium and vitamin D.

If we like the particular food, we’re happy to get our nutrients from it. But if we don’t like that food—spinach, or Brussels sprouts, or sweet potatoes—we think it’s fine to skip it as long as we take a supplement with the same amounts of these nutrients. But even recent reductionist research has shown that supplementation doesn’t work. As it turns out, an apple does a lot more inside our bodies than all the known apple nutrients ingested in pill form. The whole apple is far more than the sum of its parts. Thanks to the reductionist worldview, however, we don’t really believe the food itself is important. Only the nutrients contained in the food matter.

This belief is reinforced every time we read the labels on food packages. Sometimes these lists are quite extensive; the typical food label lists a lot of individual nutrients, with precise amounts per serving shown for each component (see Figure 5-2).

I was a member of the 1990 National Academy of Sciences (NAS) expert panel assigned by the FDA to standardize and simplify the food-labeling program. Two schools of thought existed on our panel. One view favored using the label to tell customers how much of each of the many nutrients is inside. The other, to which I subscribed, intended to minimize quantitative information on the label. I believed that we would serve the public best by providing some general information, like a list of ingredients, while staying away from the finer details. (My school of thought lost, although our report did end up proposing a labeling model that was more focused than the original.)

FIGURE 5-2. A typical example of a food label⁴

Ingredients are important, and not just for avoiding ones to which you might be allergic. You probably don’t want to eat foods with long lists of unpronounceable words, and I assume you’d like to know if your breakfast cereal contains large quantities of high-fructose corn syrup. But including fine-print details like the number of micrograms of niacin performs two disservices to the public that can lead to poor eating choices. First, it overwhelms consumers and causes most of them to ignore the labels entirely. Second, it implies that the nutrients included on the label (a minuscule percentage of the total known nutrients) are the only important ones—indeed, perhaps the only ones that exist.

This isn’t the only way the government supports and furthers reductionist nutritional philosophy. A very public example is the effort expended for many years to develop a nutrient composition database that includes all known foods. Since the early 1960s, the U.S. Department of Agriculture has been working on an enormous database in which each food is accompanied by an extensive list of the nutrients it contains and their amounts. This database is now available on the Internet for the public’s use, at http://ndb.nal.usda.gov.

Government scientists have also promoted reductionist nutritional policy through their nutrient recommendations, which focus on the quantities of each nutrient deemed important for good health—and these nutrient recommendations have a much further reach than an online database. Every five years, the NAS’s Food and Nutrition Board reviews the latest science to update these recommendations. Generally known as recommended daily allowances (RDAs), they were revised in a 2002 report to provide not single-number RDAs, but ranges of intake to maximize health and minimize disease (now called recommended daily intakes, RDIs). Trouble is, RDIs still focus on individual nutrients. And these recommendations, expressed as numbers, now serve as quality control criteria for public nutrition initiatives like school lunch programs, hospital food guidelines, and other government-subsidized food service programs.

Armed with both these government recommendations and that vast nutritional database, consumers can now look up their RDIs and then cross-check them against the database to determine what foods to add or subtract in order to achieve proper nutrient intake. The RDI creators must wonder how our ancestors, without access to computers, were able to eat well enough to survive and reproduce!

Of course, nobody chooses their diet based on databases and RDIs. But quantifying foods this way reinforces the impression that this is the best way to understand nutrition, and the fear engendered by those reductionist tools leads many people to worry about not getting their daily nutrient allowances. Hence Americans spend $25–$30 billion or so each year (as of 2007) on nutrient supplements.⁵ Many consider the use of these products to be the essence of modern nutrition. Similarly, foods have long been fortified with specific nutrients like iron, selenium, calcium, vitamin D, and iodine, because certain areas of the world or groups of people suffer from deficiencies of them. In the case of serious nutritional deficiencies, like nineteenth-century British sailors suffering from scurvy due to the lack of vitamin C, or impoverished Third World villagers dying from protein deficiency, attention to individual nutrients makes some sense. In the case of malnutrition, a supplement can save lives in the short run by buying time to set up longer-term systems that provide sufficient and balanced nutrition from real food. But for most Americans who suffer from too much food and too much granular information about that food, this approach is misguided. It overwhelms us and keeps us, in motivational speaker Jim Rohn’s memorable phrase, “majoring in minor things.”

WRENCHES IN THE REDUCTIONIST MODEL

In short, virtually all of us, professionals and laypeople alike, talk about nutrition, study nutrition, sell nutrition, and practice nutrition in reference to specific nutrients and, oftentimes, to specific quantities. We fixate on the amounts. Vitamins. Minerals. Fatty acids. And of course, the biggest obsession of them all: calories.

We’ve seen where this obsession comes from, and it’s easy enough to understand. After all, most people want to be healthy and feel good, and we’re taught that our health partially depends on getting precisely the right amount of these things into our bodies. So whether it’s the obsessive calorie counting of Weight Watchers or the 40/40/30 absurdity of the Zone diet, we believe that the more accurately we track our inputs, the more control we have over the output: our health.

Unfortunately, that just isn’t true. Nutrition is not a mathematical equation in which two plus two is four. The food we put in our mouths doesn’t control our nutrition—not entirely. What our bodies do with that food does.

Wrench #1: The Wisdom of Our Bodies

Are you sitting down? Because I need to explain something that almost no one acknowledges about nutrition: there is almost no direct relationship between the amount of a nutrient consumed at a meal and the amount that actually reaches its main site of action in the body—what is called its bioavailability. If, for example, I consume 100 milligrams of vitamin C at one meal, and 500 milligrams at a second meal, this does not mean that the second meal leads to five times as much vitamin C reaching the tissue where it works.

Does this sound like bad news? To reductionists, it certainly does. It means that we can never know exactly how much of a nutrient to ingest, because we can’t predict how much of it will be utilized. Uncertainty: a reductionist’s worst nightmare!

Actually, this is very good news. The reason we can’t predict how much of a nutrient will be absorbed and utilized by the body is that, within limits, it depends on what the body needs at that moment. Isn’t that amazing? In more scientific language, the proportion of a nutrient that is digested, absorbed, and provided to various tissues and the cells in those tissues is mostly dependent on the body’s need for that nutrient at that moment in time. This need is constantly “sensed” by the body and controlled by a variety of mechanisms that operate at various stages of the “pathway,” from nutrient ingestion to nutrient utilization. The body reigns supreme in choosing which nutrients it uses and which it discards unmetabolized. The pathway taken by a nutrient often branches, and branches further, and branches further again, leading the nutrient through a maze of reactions that is far more complex and unpredictable than the simple linear model of reductionism would suggest.

The proportion of ingested beta-carotene that is actually converted into its most common metabolite, retinol (vitamin A), can vary as much as eight-fold. The proportion converted also decreases with increasing doses of beta-carotene, thus keeping the absolute amounts that are absorbed about the same. The percentage of calcium absorbed can vary by at least two-fold; the higher the calcium intake, the lower the proportion absorbed into the blood, ensuring adequate calcium for the body and no more. Iron bioavailability can vary anywhere from three-fold to as much as nineteen-fold. The same holds true for virtually every nutrient and related chemical.

In brief, the relationship between amount consumed and amount used for virtually all nutrients is not a linear relationship. Although many professionals know this, few fully appreciate the significance of this complexity. It means nutrient databases are not nearly as useful as one might think. It also means reductionist supplementation with large doses of discrete nutrients does not guarantee the utilization of those nutrients. (In fact, our digestive processes are so complex and dynamic that super-dosing with a single nutrient all but guarantees an imbalance of some other nutrients, as we’ll see in Wrench #3 later in this chapter.)

Wrench #2: The Variability of Foods

Not knowing how much of a given nutrient will be used by the body is only part of our uncertainty. The nutrient content of the foods we eat themselves varies far more than most of us realize. Look at the research just on one antioxidant vitamin, beta-carotene (and/or its related carotenoids). Beta-carotene content in different samples of the same food is known to vary three- to nineteen-fold, although it may be up to forty-fold or more, as was reported for peaches. That’s right—you could hold a peach in each hand, and the one in your right hand could easily contain forty times more beta-carotene than the one in your left, depending on things like season, soil, storage, processing, and even the original location of the fruit on the tree. And beta-carotene is far from the only example. The “relatively stable” calcium content of four kinds of cooked mature beans (black, kidney, navy, pinto) ranges 2.7-fold—from 46 to 126 mg—per cup.

The variation in food nutrient content and the variation in nutrient absorption and utilization by the body compound each other. A simple exercise might help to make the point. Suppose the amount of beta-carotene in a carrot varies about four-fold, and the amount of this uncertain proportion that is then absorbed across the intestinal wall into the bloodstream varies another two-fold. This means that the amount of beta-carotene theoretically delivered to the bloodstream from any given carrot on any given day might range as much as eight-fold.

These are huge but uncertain variations, and whether these ranges are two- or forty-fold, the ultimate message is the same: With the consumption of any particular food at any particular moment, we cannot know with any precision how much of any nutrient is actually available to our bodies, or how much our bodies actually use.

Wrench #3: The Complexity of Nutrient Interactions

But wait—there’s more uncertainty! You may be surprised to learn that the three nutrients mentioned above can modify one another’s activities. Calcium decreases iron bioavailability by as much as 400 percent, while carotenoids (like beta-carotene) increase iron absorption by as much as 300 percent. Theoretically, in comparing a high-calcium, low-carotenoid diet with a low-calcium, high-carotenoid diet, we might see an 800–1,200 percent difference in iron absorption. But even if this theoretical variation were only 100–200 percent, this is still huge; for some nutrients, tissue concentrations varying by more than 10–20 percent can mean serious bad news.

Interactions among individual nutrients in food are substantial and dynamic—and have major practical implications. An outstanding review by researchers Karen Kubena and David McMurray at Texas A&M University summarized the published effects of a large number of nutrients on the exceptionally complex immune system.⁶ Nutrient pairs that were found to influence each other and in turn, to influence components of the immune system include vitamin E–selenium, vitamin E–vitamin C, vitamin E–vitamin A, and vitamin A–vitamin D. The mineral magnesium influences the effects of iron, manganese, vitamin E, potassium, calcium, phosphorus, and sodium, and through them the activities of hundreds of enzymes that process them; copper interacts with iron, zinc, molybdenum, and selenium to affect the immune system; dietary protein exerts different effects on zinc; and vitamin A and dietary fat affect each other’s ability to influence the development of experimentally created cancer.

Even closely related chemicals within the same chemical class can greatly influence each other. For example, various fatty acids affect the immune system activities of other fatty acids. The effect of polyunsaturated fats (found in plant oils) on breast cancer, for example, is greatly modified by the amount of total and saturated fat in the diet.

The fact that magnesium has already been shown to be an essential part of the function of more than 300 enzymes speaks volumes about the possibilities for the almost unlimited nutrient interactions. The effects of these interactions on drug-metabolizing enzymes and on the immune system also apply to other complex systems, such as the hormonal, acid–base balance, and neurological systems.⁷

The evidence cited here represents only an infinitesimally small fraction of the total number of interactions operating every moment in our bodies. Clearly, the common belief that we can investigate the effects of a single nutrient or drug, unmindful of the potential modifications by other chemical factors, is foolhardy. This evidence should also make us extremely hesitant to “mega-dose” on nutrients isolated from whole foods. Our bodies have evolved to eat whole foods, and can therefore deal with the combinations and interactions of nutrients contained in those foods. Give a body 10,000 mg of vitamin C, however, and all bets are off.

THE POINTLESSNESS OF REDUCTIONIST PRECISION

Even in this discussion of the variability of nutrient absorption, you may have noticed, I’ve still toed a fairly reductionist line. I’ve examined variability in terms of single nutrients and how much their quantities vary in food and at their site of action in the body. As we’ve seen, consuming two nutrients simultaneously typically affects the utilization of both. This variation becomes orders of magnitude more complex and uncertain when combinations of a large number of nutrients are simultaneously consumed (also known as “eating food”). Now we’re talking not just about three or so different nutrients affecting each other and the various systems of the body; we’re talking about all the active elements of a whole food. We simply cannot know how many kinds of chemicals are consumed in a single morsel of food or at a single meal or during the course of a day. Hundreds of thousands? Millions? The complexity increases virtually without limit.

If we had to rely on our brains to figure out what to eat, in what quantities, and in which combinations, or risk malnutrition or disease, the human race would have died out long ago. Luckily, our task is considerably simpler. When we eat the right foods, in amounts that satisfy but don’t stuff us silly, our bodies naturally metabolize the nutrients in those foods to give us exactly what we need at any given moment.

Our bodies control concentrations of nutrients and their metabolites very carefully, so that the amounts available to particular sites of action in the body often rest within very narrow ranges. For some nutrients, concentrations must stay within these limits for us to avoid serious health problems and even death. In short, the body is able to reduce the highly variable concentrations of nutrients in food into much more stable concentrations in our tissues by sorting out what’s necessary and what’s excessive.

One way to gain perspective on this discussion is to consider the “reference” ranges of a few nutrients in our blood plasma, as illustrated in Figure 5-3. You may have seen these ranges on your clinical lab report at the doctor’s office. Based on analyses of the blood of presumably healthy people, these ranges are generally considered “normal.” But notice how narrow these ranges vary—only 1.1–2.3-fold, compared with the five- to ten-fold (or more) nutrient variation in food.

FIGURE 5-3. Reference ranges for blood tests⁸

In short, your body is constantly monitoring and adjusting the concentrations of nutrients in the food you consume in order to turn massive variability into the narrower ranges it requires to be healthy.

CATCHING A BALL

This sounds like a lot of work for the body to be doing, I know. But that’s what it’s built for. That’s what it does best. And it does it without requiring any amount of conscious intervention in the process.

Think about the simple act of catching a ball that someone has tossed to you. Do you have any idea how complicated that process is? First, your eyes have to notice the object and identify it as a ball and not, say, a swarm of hornets or a balloon filled with petroleum jelly. Then your eyes, working in binocular fashion, begin sending a dizzying array of data to your brain to help determine the size and velocity of the ball. Even if you failed high school geometry, your brain calculates its parabolic path. Even if you flunked physics, your brain calculates the mass, acceleration, and force of the ball. And while your brain is processing all this information, it’s also communicating with the nerves that control your arm and hand, the stabilizing muscles of your back, neck, and legs, and the parasympathetic nervous system that may need to calm you down following the initial sight of an incoming projectile.

Your body is amazing at juggling all these myriad inputs and orchestrating a perfectly timed response: your arm reaches and your hand closes around the ball. But imagine if someone insisted that the right way to learn how to do this was to do all the math and physics. To measure and calculate the velocity, parabolic arc, wind speed, and everything else. School curricula around “catching” would proliferate; educators would argue about which methods work best. About 1 percent of students would excel at this methodology, while the vast majority of us would walk around getting pelted by balls that we couldn’t catch if our lives depended on it. Whenever we came across cultures where everybody could catch, we scientists would study their physiology and the materials used in making their balls and their public policy around the topic of catching, hoping to unravel the mystery and find the “cure” for ball dropping.

Focusing on individual nutrients, their identities, their contents in food, their tissue concentrations, and their biological mechanisms, is like using math and physics to catch balls. It’s not the way nature evolved, and it makes proper nutrition far more difficult than it needs to be. Our bodies use countless mechanisms, strategically placed throughout our digestion, absorption, and transport and metabolic pathways, to effortlessly ensure tissue concentrations consistent with good health—no database consultation required. But as long as we let reductionism guide our research and our understanding of nutrition, good health will remain unattainable.