Beans: Protein, cyanide, and music
First, the good: At roughly 22% protein, beans contain more than any other edible seed, and are the absolute cheapest form of protein to buy. Beans also contain a respectable amount of carbohydrates, as well as dietary fiber.
Beans supply every essential amino acid with the exception of methionine, which, conveniently, is found in corn, rice, and meat.
Katherine Czapp, writing for the Weston A. Price Foundation, says,
The high protein content of legume seeds, such as in beans, peas and lentils, make them a potential source of high quality nourishment, enhanced by impressive stores of minerals, including magnesium, potassium, phosphorus, iron and molybdenum, as well as B vitamins such as folate and thiamine. All legumes contain both omega-3 and omega-6 fatty acids, with kidney and pinto beans particularly high in omega-3.
Beans are clearly a highly nutritious food, and a filling one.
Now the bad. Here’s a short list of toxins found in many common bean varieties:
Cyanide
Lectins
Phytic acid
Protease inhibitors
Oligosaccharides (raffinose, stachyose, and verbascose)
Cyanide, as scary as it sounds, is found in most beans, but only in trace amounts. Lectins can seriously damage your gut, phytic acid ties up nutrients so your body can’t absorb them, and protease inhibitors get in the way of protein digestion. However, the traditional preparation methods that we are about to discuss — soaking, fermenting, sprouting, and cooking — reduce the amount of these toxins in beans to negligible levels.
But let’s not forget the elephant in the room, the large, complex, and undigestible sugars known as oligosaccharides. Mammals (that’s us, folks) lack the enzyme (alpha-galactosidase) required to break them down, so they ride with impunity through our stomach and on into the lower intestine, where they serve as a sort of party snack for anaerobic bacteria, resulting in all kinds of socially awkward, um, results.
Fortunately, there are all kinds of techniques to minimize the odorous byproduct of oligosaccharides and achieve significantly better results with your beans.