Soy

• "The first principle is that you must not fool yourself, and you are the easiest person to fool."

  • - Richard Feynman

I am vegetarian by choice, and would be pure vegan if I felt that was healthy, practical, and non-confrontational. However, "pure" is usually a formula for confrontation, and I have more important battles to fight. Vegetarian is more healthy overall.

Many insist that fish is needed for a healthy diet. If so, the stark choice is between a peaceful planet, and some fish for the wealthy for another decade or two. I'll revisit that option when fish farming drastically improves, perhaps farmed Tilapa bred and fed for high omega-3 content and high food conversion efficiency. I expect more efficent results from gene-engineered algae.

"Sustainability" is the label applied to the notion that if we use our planet up more slowly, it might last long enough for our grandchildren; those brandishing the sustainability label rarely calculate thousand-year effects. I think about billion-year timescales - life on the Earth must survive long enough to replicate in other star systems, which will take a very long time to accomplish. Let's use another term, "Perpetuality', for the very long term perpetuation of life, by natural AND artificial means. Perpetuality means "make more than you (and others) use up". or "Make more, use less".

Humans are a significant fraction of the animal biomass on the planet, but our food animals (mostly cows, pigs, and chickens) greatly outweigh us. In small numbers, these animals can maintain grasslands, renew the soil, and control insect pests. In their current vast numbers, vast acreages of cropland are used to feed them, halving the food available for humans, while destroying wilderness.

All this suggests a near-vegan diet, with some cattle to consume (some of) the grass that we cannot. Frankly, I have not calculated the amount of grassland this is, or the optimum amount of grazing. Numbers needed!

It is possible (but seems unlikely) that the optimal amount of grazing is zero - perhaps perpetuality demands a vegan diet. If so, our next decision is about protein sources.

Soy is among the highest protein legumes, and seems a likely source. Sedentary humans need fewer calories per gram of protein, and lupin beans offer the highest ratio of protein grams per calorie. They are also laced with toxic alkaloids, and must be carefully prepared before eating. This is an important clue. Plants make seeds for propagation, not animal consumption, and protect those seeds from insects with hard husks or toxic chemicals. How does soy protect itself?

According to some researchers, the phytoestrogens genistein and daidzein in soy beans interfere with growth and reproduction of insects. A biochemist friend says they do the same thing in humans, interfering with the formation of axons and dendrites in the brain. The Honolulu-Asia Aging Study, focused on the effects of the Asian diet on heart health, found that moderate midlife tofu consumption reduced the average age of onset for dementia. This 2000 paper brought a halt to my previously high soy consumption. In my 40's, this may have been closing the barn door after the horses escaped, but perhaps a few nags remain inside.

Soy protein isolate offers very high protein to carbohydrate ratios, but does not remove the phytoestrogens. At 0.9 g/kg, soy protein is more like a pharmaceutical than a food.

Before the 20th century, the east Asian diet was meager, almost all vegetables. Soy tofu was a food for the rich, and for celebrations; not consumed in kilogram-per-month quantities. Few people ate enough soy for long enough to match the "moderate" levels observed in the Honolulu study. High soy consumption is a 20th century invention.

My biochemist friend told me that before the 1960s, soy was grown for ink and animal feed. Humans pay more for food, so soy marketing companies like Archer Daniels Midland created the notion that soy was a health food, and fostered the myth of high historical levels of Asian soy consumption.

In my ideal world, we would develop methods to remove the phytoestrogens from soy protein isolate (probably a microbe that gobbles them up, or produces an enzyme that degrades them). It might be possible to genetically engineer soy without the phytoestrogens, but that will lower the insect resistance and increase the need for pesticides. However, the soy protein advocacy community includes many anti-bioengineering zealots, and is easily manipulated by myths created by marketers seeking to isolate and overcharge them. The meat-advocate "paleo" community shuns soy AND bioengineering.

Perhaps there are enough science-loving environment-loving realists out there to create a market for "ZPO3--SPI" - zero-phytoestrogen omega-3 soy protein isolate. Given that, I would stop consuming dairy and whey, and move closer to pure vegan. Until then, grass-fed milk and cheese, with surplus calves sacrificed for our sins.