Friday, October 10, 2008


My fuel costs savings may be marginal, but I do get to eat a lot of food and stay thin. As I've increased my activity level these last two years my views on nutrition have changed substantially.

As a child I ate cold cereal for breakfast nearly every morning. My mom stocked the pantry solely with so-called adult cereals, and so I grew up eating cheerios, raisin bran, and the like. I liked grape nuts even when I was very young, thus showing flashes of what would develop into a lifelong obsession with fiber intake. I ate prodigious quantities of cereal from a young age, refilling the bowl with more flakes, nuts, or ohs after finishing the first and sometimes even adding more milk to keep the cycle going. I kept the cereal box on hand next to the newspaper page I was reading so that I could pour on demand with minimal interruption. And this is how I discovered the standard nutrition label.

One of my earliest memories of the nutrition label is that at an early age -- about ten or so -- I discovered for myself the caloric density of fat, carbohydrates, and protein based on comparing the stats from different cereals' nutrition labels. I still think this was a clever trick of algebra -- solving for three unknowns, no less! -- being as how I didn't then know what algebra was. So what that I miscalculated fat to have eight kcal per gram instead of the actual nine. I learned it was nine instead of eight when they started printing the densities in fine print shortly thereafter.

To me, those nutrition labels were law. Each food was broken down into its constituent components along with recommended allowances, and one could then construct a healthy diet by selecting foods that added up to meet those recommendations. Those labels remained law for me until recently when a certain weight-lifting, food-optimizing reductionist began revealing to me the terrible inadequacies of the nutrition label. It started with the glycemic index.

The glycemic index shows quite clearly that carbohydrates are most certainly not equal. Of course, I had long known that sugar is generally bad, but then an orange is two-thirds sugar by calorie yet is low on the index and is healthier than, say, raisins, which are high on the index. It turns out that fiber sometimes can be healthy more than sugar can be unhealthy. Except that some sugars are healthier than others. And not all fiber is the same. And so it goes, each food having its own special cases and subtleties. Why doesn't the standard nutrition label address these issues? Why not at least put the glycemic index on the label? It turns out that even the glycemic index is not a perfect indicator and there are exceptions to it as well. The body absorbs barley much slower than wheat even though both have roughly the same glycemic index value, and milk is insulin-tropic despite being mostly fat and protein.

It's an interesting question to ponder what information the standard nutrition label should include to maximize the conveyance of health information without increasing the label's size. Here's one thought: each food item should list the year that that food was first known to be eaten by a sizable number of humans. For example, oatmeal was first consumed a few thousand years ago, and store-bought cookies made with sugar substitutes are a modern invention; I consider this a big clue that our evolved genotypes aren't well suited for eating low-fat store-bought cookies.

Yes, my principal heuristic for nutrition is this: if humans weren't commonly eating it a thousand years ago or earlier, then it probably isn't healthy. This is a good rule in that it disqualifies most foods in the grocery store and thus makes one's choices much simpler. Anything with trans fats, corn syrup, or polysyllabic-named preservatives is thrown out. What remains are foods that are shipped in boring packages that you must cook in your own home. These also happen to be many of the cheapest foods in the store and the ones with the most potential to satisfy one's appetite.

The heuristic's inverse is not true, however. There are indeed some foods that have been around for thousands of years and are not particularly nutritious. The three big ones in the United States, I think, are: corn, wheat, and rice. These are not bad foods, but they have substitutes that are much better. Enter quinoa, the super grain.

Quinoa may be the most remarkable of grains. It has moderate fiber content; it's low on the glycemic index (low 50s); it has high protein for a grain (about 12-15% by calorie); and most extraordinarily it's a complete protein source by itself. Its texture and taste makes it a great substitute for rice in any context, and it also works well as a hot cereal by itself. Empirically I've observed that quinoa delivers a steady, slow burn and is thus ideal before long bicycle rides. It would probably make a great on-the-bike food, but I have yet to figure out a way to work it into a solid bar that wouldn't make a mess.

I'd rather not prattle about all my favorite foods, but I must make mention about one more super food: flaxseed meal. Flaxseed meal is potent stuff, and I put it in everything I cook that warrants a bit of a nutty flavor. Flaxseed's primary claim in nutrition is that it contains omega-3 fatty acids, which are only found in sufficient quantity in a small number of other foods such as fish, organic dairy and meats, and walnuts. Flaxseed also is rich in fiber and protein and has a good amino acid profile. It's a food that I feel a person can't go wrong with, although Wikipedia claims that overconsumption can lead to diarrhea. Empirically I have no cause to disagree with this claim, and that is Too Much Craig.

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