Nutrients: Macro- and Micro-
I'm halfway through reading Michael Pollan's book, In Defence of Food. It's a great read, an interesting and entertaining overview of the modern Western diet and how we got to where we are, in a society where Type 2 Diabetes has become so common, it even has its own magazine. The book is not too scientific but he cites sources so you can read the original book or document he got information from. I always like that in an author.
Something I learned seems pretty basic, but I'd never known this before. I've heard about micronutrients a lot. These are vitamins and minerals we get from our food that we need for healthy functioning, but we don't need a lot of. We need some salt, but not too much. A deficiency of iron is anemia, and that's bad, but too much iron is also bad. Most nutrients come from our food, but one of the major micronutrients, Vitamin D, comes from the sun. Actually, from sunlight on our skin, and the interaction creates Vitamin D. We need to maintain the proper ratio of Vitamin D to Vitamin A and other micronutrients in order for our bodies to function properly.
Okay, so I already had a sense of what micronutrients are, those mysterious little substances we need but can't see.
What I'd never quite grasped is macronutrients. It turns out this is very obvious, we just rarely use this term. Macronutrients are the primary nutrients in food: protein, fat and carbohydrate. Oh. Well, I guess i *DID* know that!
Macronutrients were the first elements in food to be identified, as you might imagine. What I didn't know is that the scientists who discovered them also said, now that we knew this about food, there was nothing else we needed to know. One scientist created an infant formula based on his knowledge of macronutrients, but infants did not do well on it. It turned out there were, in fact, other things left to discover about food.
Micronutrients were discovered, and with each discovery, scientists often claimed we knew it all, there was nothing else we needed to know. Based on the science of nutrition, food manufacturers began to break foods down into their component parts, and if something seemed to be lacking in the refined or processed version, they would add that back in. Based on the assumption that what we know today is all there is to know about this topic.
This notion that we know all there is to know about food, so we talk about food in those terms, Pollan calls "Nutrition-ism." All of us talk about food this way today: "low carb diet," "low fat," how many calories something has. And we've lost touch with the food traditions of the past, that told us too much dessert made people fat and too much red wine gave you gout, if you planned to get pregnant, eat more liver and so on. Now we talk about how much protein and how many carbs something has. We read labels on food as if they mean something.
Pollan is saying that perhaps food cannot be reduced to macro- and micro-nutrients. Perhaps there is more complexity in any food than we can analyze in a scientific way. One of the advantages of the scientific method is the way it can formulate a question so that it can be answered. This often means isolating something so it can be measured, even if that's not how the thing actually functions in real life. One of the disadvantages of the science of nutrition is that how humans (or animals for that matter) fare on certain foods or with certain diets is very complex, not easily broken down into simpler forms. If you eat a whole fruit, say an apple, your blood sugar will not rise as quickly as if you made the same apple into juice and drank that. If you break that apple down into its various nutrients, and consume the equivalent sugars and starches and micronutrients in pure chemical form, your body will react entirely differently than if you just eat the apple. Well, why? What's going on in a whole fresh apple that isn't going on with its simplest building blocks?
Pollan says that real food is complex. Far more complex than any amount of science has so far been able to analyze. As time has gone on and science has progressed, we've realized that plain white flour is lacking in nutrients, so most flour is now fortified. But is even that the same as wheat that includes the wheat germ or kernel?
The problem for us in the industrialized West is that, for various reasons, we've been led to see food as components, as sources of nutrients rather than as complex, tasty, nourishing food, that maybe cannot be broken down into simpler elements without missing some essential point about it as food. Recently I said to someone "there is no possibility that 100 calories of steak can have the same nutritional value as 100 calories of jelly beans." They replied, "that's a very political statement." And it is. Because the food industry spends a great deal of money developing new products and improving old ones, hoping to tempt us to buy what they sell. A lot of people benefit from having us believe that a processed food is the same nutritionally as a whole food. Somebody somewhere would be very happy, and very rich, if they developed a jelly bean that could be marketed as having the same nutrition as a steak,.
Researchers have studied how people ate in other societies than our own, and whether they were healthy or not. It turns out human beings have adapted to widely varying diets, from almost 100% animal -based to mostly plant-based, and humans can thrive on very different diets. However, science itself testifies that the one diet we cannot thrive on is the modern Western diet, which is the fundamental point of Pollan's book. We're seeing epidemics of Type 2 Diabetes, obesity, cardiovascular disease, increases in Alzheimer's and cancers, that were unknown in previous centuries and are much less common in cultures that eat differently. It seems clear diet has a great deal to do with health.
Pollan makes the case that real food is more complex than processed food, and likely contains nutrients that haven't been discovered by science yet. Sometimes, it's not the nutrient in isolation that we need, it's a dynamic balance between nutrients. Omega 3 fatty acids are all the rage right now, but it turns out it's not so much that we need X amount of Omega 3 so much as we need to maintain the correct balance between Omega 3s and Omega 6s, along with other fats. Just as we'll get more benefit from eating that apple or orange than from the juice made from it, and way more than if we eat the same nutrients in an artificially created form, we can't possibly keep track of all the nutrients we need to eat al the time.
And it's even less likely the average person can keep track of all the different studies being undertaken by scientists, or the advice given out by experts.
Maybe we just need to eat food, not worry too much about calories or macronutrients. Food is about more than nutrition, as narrowly defined by scientists whose job is to define things as narrowly as possible. Food is comfort, it's family, pleasure, culture and tradition.
I haven't finished In Defense of Food yet. I've just started the section on how to escape the Western diet. Stay tuned....
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I'm easily amused. I try to be positive about things, yet I am also driven to distraction by irrationality. Especially if the purpose is valid, but could be achieved with less drama. You'll see all of this in my writing!