Today’s post starts as a fun biology lesson; it turns out that a scientific understanding of digestion gives us unexpected guidance about cooking. And–here’s the kicker–that same lesson applies to neuroscience and teaching. Let me explain.
The Science of Cooking
I recently read an article that outlines the three core concepts in digestion: a) pushing, b) acid, and c) base. Yes, it’s that simple. At its core, “digestion” is the process of pushing food from a highly acidic environment to a highly basic environment.
More specifically, digestion starts when peristalsis (that’s a fancy word for “pushing”) moves food down into the stomach. There, hydrochloric acid breaks down proteins and kills off harmful bacteria. We’re talking a pH of 1.5-3.5 here. Next, peristalsis continues pushing food into the highly basic environment of the small intestine. The addition of bicarbonate from the pancreas shifts the pH to somewhere in the 7-8.5 range. This simple, 3-part process–“pushing from acid to base”–frees the key nutrients from our food and ultimately allows us to thrive.
Now, the magic begins. Chefs who understand the biology of digestion can mirror these essential steps in their cooking.
Expert chefs recognize that cooking–like digestion–should be a pushing/kneading process. To mirror the hydrochloric acid of the stomach, that process should begin in a highly acidic environment . After the food has been kneaded in acidic lemon juice or vinegar, it should then be switched to a highly basic preparation medium: perhaps baking soda or lye.
This food preparation process–which recreates core biological processes of digestion–offers flexible and scientifically-informed guidance for all chefs: from novice to Michelin-starred.
There’s your cooking lesson for today. To prepare food like an expert, “push food from acid to base.”
One More Thing
Here’s an essential additional point. The description of digestion above is accurate enough for this blog post; the cooking advice below it is entirely nonsense. Seriously: just imagine a chicken breast drenched in vinegar and then soaked in lye. Bon appetit?
Chefs don’t prepare good food by recreating the internal process of digestion. They do so by choosing the right ingredients and preparing them in appropriate ways. We get no benefit whatsoever from recreating the internal biological/digestive process externally. Honestly, the result would be gross (at best) and fatal (at worst).
I promised above that “the same lesson applies to neuroscience and teaching.”
Consider this argument:
“When students learn math, they process information in the visual cortex, then the angular gyrus, and finally in the caudate nucleus. Our math instruction should mirror this neural chain. Start by teaching a new concept visually; then switch to factual processing; and conclude with automatic processing. Doing so reenacts the very neural processes that result in conceptual understanding!”
Even if it were true that “the brain” processes information entirely sequentially–and it’s almost certainly not true–the logic of this argument doesn’t hold. Reenacting internal brain processes outside the brain offers no benefits for the same reason that kneading mashed potatoes in pancreatic enzymes isn’t good cooking advice.
Applying Biology to Life
Applying the biology of digestion to create cooking advice requires complex, subtle, and nuanced translation. For instance: it’s good to put butter on carrots because those fats help us digest vitamin A. This guidance doesn’t recreate the internal biological process in the cooking process; it informs the cooking process with an understanding of digestion.
Applying the neurobiology of cognition to create teaching advice requires complex, subtle, and nuanced translation. For instance: it’s (probably) true that dopamine helps regulate students’ motivation levels. But telling teachers to “raise students’ dopamine levels!” overlooks the boggling complexity of motivation, of dopamine, and of students.
To take two simple examples:
- too much dopamine in the mesolimbic pathway–which connects the ventral tegmental area to the nucleus accumbens–is associated with the hallucinations of schizophrenia.
- one easy way to increase dopamine levels: cocaine.
In brief: if someone offers you authoritative teaching advice because “the brain does this when students do that,” respond by asking hard questions. For starters, ask “do we have any psychology research showing that this teaching advice has any benefits in a classroom?”
Research can and should inform our teaching practice. And: our own professional experience gives us standing to evaluate the advice we get. If digestion-based cooking advice sounds gross, wise chefs ignore it. If neuroscience-based teaching advice sounds improbable, wise teachers ask thoughtful questions.
The goal isn’t to ignore neuroscience—it’s to demand that “brain-based” advice meet the same research standards we’d apply to any other teaching recommendation. In brief: know the biology, question the advice.
