Story
The Dark Matter of Nutrition · why your liver is overbuilt
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In one pass Not one of the molecules that make garlic garlic appears on the nutrition facts panel.
Educational content, not medical advice — consult a clinician.
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Chapter 1
What the nutrition label leaves out
Not one of the molecules that make garlic garlic appears on the nutrition facts panel.
That panel was not drawn up at random. To see why it looks the way it does, start with a question about the body: what earns a molecule the name essential?
Essential is the gap between two rates
The answer is not in the food. It is in you, and it is two rates you can measure:
how fast you make ithow fast you use it up
If you make it faster than you use it, you don't need it from your meals. If you make it more slowly than you use it, the gap has to be filled by eating. If your rate of making is zero while your need is not, it is essential: cut off the supply and your body's store falls at the rate you use it, until below a certain line, the step that depends on it stops.
Look closely at the shape of this sieve. The condition for getting onto the panel is that its absence goes wrong within weeks to months.
Such a sieve is bound to miss a whole class of molecules. Being absent from the panel does not mean being absent from food, and still less does it mean doing nothing in your body.
The nutrition label is a shadow cast by acute deficiency disease.
That panel was not drawn up at random. To see why it looks the way it does, start with a question about the body: what earns a molecule the name essential?
Essential is the gap between two rates
The answer is not in the food. It is in you, and it is two rates you can measure:
how fast you make ithow fast you use it up
If you make it faster than you use it, you don't need it from your meals. If you make it more slowly than you use it, the gap has to be filled by eating. If your rate of making is zero while your need is not, it is essential: cut off the supply and your body's store falls at the rate you use it, until below a certain line, the step that depends on it stops.
Look closely at the shape of this sieve. The condition for getting onto the panel is that its absence goes wrong within weeks to months.
Such a sieve is bound to miss a whole class of molecules. Being absent from the panel does not mean being absent from food, and still less does it mean doing nothing in your body.
The nutrition label is a shadow cast by acute deficiency disease.
Evidence · What the raw-garlic panel leaves out
The US Department of Agriculture's database lists 69 rows for raw garlic. Ascorbic acid, that is vitamin C, is there; so are amino acids such as alanine. What is not on the list is allicin, the molecule that makes garlic pungent and antimicrobial; nor ajoene, nor p-coumaric acid. Yet researchers recently counted 6,802 small molecules in raw garlic (Menichetti 2024).Those 69 rows were not picked at random. Allicin and ajoene belong to the class of molecules that never makes the panel: skip garlic and you get no disease. That is exactly why they are absent, and exactly why they are easy to treat as if they did not exist.
The shadow comparison goes only this far. Nobody made the panel small on purpose. It was produced by a question, and that question was will its absence kill, not what is actually in here.
Mechanism · Why the label reads like a medical history
What stopping looks like is visible. Cut off vitamin C and you cannot build stable collagen, so gums bleed and wounds split open; that is scurvy. Cut off thiamine (vitamin B1) and your nerves and heart cannot get at the energy in sugar; that is beriberi. Niacin and vitamin D each fail in their own way.So the label is a medical history
That condition selects a very particular class of molecules: ones the body cannot build, without which some step in the body stops turning. Twentieth-century nutrition found them by following these diseases one at a time: first the disease, then the molecule.
Turn that around and the sieve is bound to miss a whole class: molecules whose absence causes no trouble within weeks. They have no matching deficiency disease, so nobody traced a disease back to them, so they are not on the list.
Numbers · How much is tracked, how much is not
Pull the camera back and the width of this shadow can be measured.The core panel the US Department of Agriculture has long tracked is 150 essential micro- and macronutrients, organized mainly around energy metabolism and deficiency: fatty acids, amino acids, sugars, fiber, minerals and vitamins. Since 2003 it has also reported flavonoid content for selected foods, extending the main panel to 188 components (Menichetti 2024).
Set that against the whole of food chemistry:
In 2019 the food compound database FooDB held 26,625 compounds. Those 150 are about 0.5% of it. In other words, more than 99% of the biochemicals in food go untracked by any national database, and many of them have documented roles in health and disease (Barabási 2020).By 2024, after integrating the literature, mass-spectrometry repositories and experiments, composition databases and pathway predictions, the library had become 139,443 molecules: 92,612 detected and 46,831 inferred (Menichetti 2024).
But those two numbers cannot simply be laid side by side; first you have to say what each one is. 26,625 is what FooDB held in 2019. 139,443 is not that same database grown up; it is a separate library the authors assembled (FooDB itself held about 71,000 by 2023). More important, 46,831 of them are inferred: computed from metabolic pathways and from how closely species are related, not measured in food.
So using these two numbers to say that scientists estimate between twenty thousand and a hundred and thirty thousand compounds in food reads two different rulers as a single error range. The honest sentence is only this: the hundred-odd nutrients we track are a rounding error on any ruler anyone has picked up.
Back to raw garlic: 69 rows against 6,802 molecules, of which 1,984 were actually detected and 4,818 inferred. Count only the detected column and it is still 69 against 1,984. FooDB also records how many known bioactivities each molecule has: the alanine on the panel has 3 and ascorbic acid 105, while the absent allicin has 64, ajoene 46 and p-coumaric acid 24 (Menichetti 2024). The missing ones are not nobodies.
A previous case
This has happened once before. In the 1980s, opponents of the Human Genome Project argued that only the coding regions (the stretches of DNA that directly spell out protein recipes) were worth the cost of decoding. Those regions are 1.4% of all base pairs; the remaining 98.6% they called junk DNA. Today it is estimated that 66% of disease-causing variants sit in exactly those non-coding regions (Barabási 2020).
This comparison, too, goes only so far. It does not predict how many treasures hide among those hundred-odd thousand molecules. It makes one point: a list filtered for a purpose is easily mistaken for the whole. And the purpose that filtered the nutrition label was finding what brings people down within weeks.
Chapter 2
Liver enzymes that grab the unknown
You would not build a clumsy-handed enzyme for a molecule you already know.
Your liver cells hold a large family of enzymes called cytochrome P450. Their job is to cut a handle onto a foreign molecule: they press an oxygen atom onto it, creating a point where something else can be attached (Guengerich 2008).
The odd thing is that they do not grip precisely. They are not a lock that accepts only one key. They are a hand that can change shape to grab things. Gripping imprecisely makes them slow and costly, but it lets them grab things they have never seen.
The body is perfectly able to build specific proteins: the doorway in the small-intestine wall that carries glucose recognizes glucose almost exclusively. Why does one body use two ways of building?
Because they face different kinds of problem. Glucose's list has one entry, and it never changes, so a protein can be tailored to it. The list P450 has to deal with is not known to the body in advance, and it changes with every meal. You cannot tailor a lock to a molecule you have never seen.
From this follows the foundation of this whole story: the non-specificity of these enzymes is itself the fingerprint that unknown molecules exist.
Your liver cells hold a large family of enzymes called cytochrome P450. Their job is to cut a handle onto a foreign molecule: they press an oxygen atom onto it, creating a point where something else can be attached (Guengerich 2008).
The odd thing is that they do not grip precisely. They are not a lock that accepts only one key. They are a hand that can change shape to grab things. Gripping imprecisely makes them slow and costly, but it lets them grab things they have never seen.
The body is perfectly able to build specific proteins: the doorway in the small-intestine wall that carries glucose recognizes glucose almost exclusively. Why does one body use two ways of building?
Because they face different kinds of problem. Glucose's list has one entry, and it never changes, so a protein can be tailored to it. The list P450 has to deal with is not known to the body in advance, and it changes with every meal. You cannot tailor a lock to a molecule you have never seen.
From this follows the foundation of this whole story: the non-specificity of these enzymes is itself the fingerprint that unknown molecules exist.
Mechanism · What a specific transporter looks like
Start with a protein that is not clumsy, for contrast.The wall of your small intestine carries a transporter protein that moves glucose into its cells, the sodium-glucose cotransporter 1 (SGLT1). It is severely picky: it is fastest with glucose, drops to a fraction of that speed with galactose, and barely moves xylose at all (Wright 2011).
Why can it afford to be so picky? Because it has no need to be otherwise. Glucose has one shape, and that shape has not changed in hundreds of millions of years. The body knows exactly whom it is waiting for, so it built a doorway that recognizes that one face. Specificity pays in speed and thrift.
Mechanism · How loosely it grips
The most famous member of the family is , a P450 that handles many drugs.It works the opposite way to that transporter. Among the human enzymes of this family, CYP3A4 takes on the widest mix of substrates (the molecules it acts on): structural studies found that its active pocket changes shape around whatever binds, and its volume can expand by more than 80% (Ekroos 2006).
Mechanism · Two builds inside one family
The family has two more equally odd properties:Humans carry 57 CYP genes, and the family splits into two populations, which says more than the total does. Only about a dozen handle foreign molecules, clustered in the CYP1, CYP2 and CYP3 families; five of those cover roughly 95% of drug metabolism (Guengerich 2008). The remaining forty-odd mostly have dedicated substrates made in the body: they build steroid hormones and bile acids, make eicosanoids (fatty signaling molecules that act locally), and activate vitamin D (Zanger 2013).And it is exactly the dozen that meet foreign molecules whose substrates overlap and which can be induced; the forty-odd on in-house duty are specific (Zanger 2013). Inside one gene family, the body builds specific enzymes for molecules it knows and broad ones for molecules it does not. The glucose transporter in the gut and this clumsy hand shrink here into a contrast within a single family.
Mechanism · Inducible, with a second step
They can be induced. When a kind of molecule keeps arriving, the body builds more of the matching enzyme. Capacity can be expanded when needed.After the handle comes a second step. Another set of enzymes welds onto the handle a large, water-loving, electrically charged tag: glucuronic acid, sulfate or glutathione (Jancova 2010). Charged things cannot slip back through a cell membrane, so once the kidney filters the molecule out, it can never sneak back in.
Mechanism · Why the design has to be broad
Against a list whose contents you do not know, specificity is meaningless. Follow that logic and the only workable design is breadth: build a hand that changes shape, let it grip anything a little and accept that it grips poorly; give it a dozen colleagues with overlapping substrates as backup; and let it scale up on demand.You would not build something this slow, this expensive and this imprecise for a known, finite list of molecules. Specificity always pays better. The most sensible reason a body would accept the cost of clumsiness is that it expects to meet molecules it has never seen, and to meet them often. This argument works backward from design to purpose; it is not a result measured in an experiment.
Background · A chemical arms race
And the fingerprint has an origin. A classic hypothesis for why the P450 superfamily split into so many members is a continuing chemical arms race between animals and plants: plants keep making new defensive molecules, and animals keep making new enzymes to take them apart (Gonzalez & Nebert 1990).If the hypothesis holds, your liver was shaped into its present form by somebody else's chemical weapons.
Who made those weapons, and why, is answered on the plant's side. The liver's two steps are covered in more detail in the Hepatic System story.
Chapter 3
Molecules plants make to fight insects
When plants made those molecules, they were not thinking of you. They were thinking about how to poison the insect chewing on them.
It only goes off when bitten
Cut open a garlic bulb or chew a mouthful of broccoli, and that sharp smell has only just appeared. An intact plant cell does not contain it.
The cabbage family shows how it works. A molecule called a glucosinolate and an enzyme called myrosinase are normally stored in different compartments of the cell, each sitting quietly. Once the cell wall breaks, the two mix, the enzyme cuts the glucosinolate apart, and an isothiocyanate forms; that is the pungency (Fahey 2001).
This is a chemical mine that goes off only when bitten: it costs nothing while idle, detonates the moment something bites, and it detonates in the mouth doing the biting.
The heat in your mouth is a stray bullet
Biochemically, you are a relative of the insect chewing the broccoli. A molecule that can disrupt its enzymes can often reach yours too; but you are far larger, so the same bite gives you a far smaller dose.
So when you eat plants, you are eating a poison prepared for someone else. By accident, not by design.
It only goes off when bitten
Cut open a garlic bulb or chew a mouthful of broccoli, and that sharp smell has only just appeared. An intact plant cell does not contain it.
The cabbage family shows how it works. A molecule called a glucosinolate and an enzyme called myrosinase are normally stored in different compartments of the cell, each sitting quietly. Once the cell wall breaks, the two mix, the enzyme cuts the glucosinolate apart, and an isothiocyanate forms; that is the pungency (Fahey 2001).
This is a chemical mine that goes off only when bitten: it costs nothing while idle, detonates the moment something bites, and it detonates in the mouth doing the biting.
The heat in your mouth is a stray bullet
Biochemically, you are a relative of the insect chewing the broccoli. A molecule that can disrupt its enzymes can often reach yours too; but you are far larger, so the same bite gives you a far smaller dose.
So when you eat plants, you are eating a poison prepared for someone else. By accident, not by design.
Mechanism · These molecules do no work for the plant
They have a collective name: secondary metabolites. Secondary means they take no part in the plant's own growth and energy production, which is called primary metabolism. Secondary metabolites are for dealing with the outside world.Of the several thousand molecules counted in raw garlic, the researchers' own words are that many are secondary metabolites acting as the plant's chemical defense against predators and extreme weather (Menichetti 2024).
Defense against whom? Insects, fungi, bacteria, the sun. Not you.
Mechanism · How the liver and the plant fit together
Now return to the question: why did your liver build a whole infrastructure for molecules it has never met?The answer may be here. Your ancestors ate other species' chemical weapons every day, for a very, very long time. The weapons kept changing, because the plants were evolving too; so the tools for taking them apart could not be custom-made. They had to be general, expandable, and broad to the point of clumsiness. The arms-race hypothesis Gonzalez and Nebert proposed in 1990 is about exactly these two things driving each other (Gonzalez & Nebert 1990). It is a hypothesis about evolutionary history: it makes sense, but it cannot be replayed as an experiment.
Mechanism · The benefit runs the other way
If the day job of these molecules is to mildly interfere with your biochemistry, then their benefit to you is unlikely to be doing your work for you. More likely, they give you a gentle poke, and your response to being poked is where the benefit comes from.That idea has a name, xenohormesis: many dietary plant chemicals are toxins the plant uses against insects and harsh conditions, but on our side, at the low doses people actually eat, they switch on adaptive stress responses in our cells, and so bring stress resistance and other benefits (Surh 2011). This is an explanatory framework proposed in a review, not a conclusion tested point by point in people.
Where exactly that poke lands, down to which atom of which molecule, is worked out best for sulforaphane in broccoli.
Chapter 4
How broccoli switches on your defenses
Going by the mechanism inside cells, what sulforaphane from broccoli does for you is not clear away free radicals on your behalf. It mildly poisons you, and that pushes your cells to turn up their own defenses. This pathway has been studied in fine detail in cells and animals; how much benefit it buys a person has not been measured directly.
Step one · An electron-poor carbon
When you chew broccoli, myrosinase cuts glucosinolate into sulforaphane; the chemical mine that goes off only when bitten has just detonated (Fahey 2001). Sulforaphane carries an electron-poor carbon that looks for anything electron-rich to crash into and then sticks to it covalently, though the bond is reversible and can come apart again. The target it hits most easily in a cell is the sulfur on the amino acid cysteine.
Step two · What it hits is a sensor
Cells carry a protein called KEAP1 with a row of cysteines. It works as a bridge: one end is attached to the machinery that dismantles proteins, the other grips a switch protein called Nrf2 and keeps handing it over to be taken apart. So the cell is making this switch all the time and destroying it all the time, like a wound-up spring held down by a hand. What sulforaphane hits is exactly that hand.
Step one · An electron-poor carbon
When you chew broccoli, myrosinase cuts glucosinolate into sulforaphane; the chemical mine that goes off only when bitten has just detonated (Fahey 2001). Sulforaphane carries an electron-poor carbon that looks for anything electron-rich to crash into and then sticks to it covalently, though the bond is reversible and can come apart again. The target it hits most easily in a cell is the sulfur on the amino acid cysteine.
Step two · What it hits is a sensor
Cells carry a protein called KEAP1 with a row of cysteines. It works as a bridge: one end is attached to the machinery that dismantles proteins, the other grips a switch protein called Nrf2 and keeps handing it over to be taken apart. So the cell is making this switch all the time and destroying it all the time, like a wound-up spring held down by a hand. What sulforaphane hits is exactly that hand.
Mechanism · Why that carbon is electron-poor
Sulforaphane carries an isothiocyanate group, written —N=C=S. The nitrogen and sulfur on either side pull electrons away from the carbon in the middle, leaving it electron-poor, which chemists call electrophilic.The two ends of the bridge are these. One is the Cul3 ubiquitin ligase, an enzyme that tags proteins for destruction. The other is a transcription factor called Nrf2, a switch protein that decides whether a set of genes is turned on. KEAP1 keeps handing Nrf2 to the ligase, and the ligase tags Nrf2 for destruction. So Nrf2 is dismantled as soon as it is made, its concentration stays low, and the genes it controls stay low too (Hu 2011).
Sulforaphane sticks covalently onto KEAP1's cysteines. Number 151 (Cys151) is among the ones it modifies most readily, and modifying it is required for sulforaphane to work (Hu 2011).
Mechanism · What happens when the hand lets go
Step three · The hand lets goOnce the bridge breaks, Nrf2 is no longer tagged, so it builds up, moves into the cell nucleus, pairs with a small Maf protein, and binds a switch sequence in the genes called the ARE (antioxidant response element). It then starts switching on a set of protective enzymes (Hu 2011).
Which enzymes? Here is an elegant loop:
Glutathione S-transferase: this is the second step in the liver, the one that welds a water-soluble tag onto the handle. What this plant toxin does is turn up the very production line that clears it.NAD(P)H quinone oxidoreductase 1 and heme oxygenase-1, two more tools that protect the cell (Hu 2011).And one that matters more: through the ARE, Nrf2 controls the rate-limiting enzyme of glutathione synthesis, glutamate cysteine ligase (GCL, built from the GCLC and GCLM subunits) (Lu 2013).
That last one is where this lands. Glutathione is your cells' main reducing agent, and one of the tags the liver's second step welds on. Sulforaphane cleared no free radical for you. It is not even a scavenger. What it did was open the rate-limiting valve on the machine that builds scavengers.
So the benefit runs the other way
Not: you swallow a scavenger and it cleans up for you.
But: you swallow a mild poison; your cell notices that something is covalently attacking its cysteines, lets go of the hand that was holding the spring down, and raises its own defensive capacity.
The benefit is built by you. The plant only pressed a button.
The button's existence makes a point too: your cells carry a sensor dedicated to noticing that an electrophile has arrived, and that sensor is wired to the master switch for defensive genes. A body is unlikely to install a sensor for something that never happens; this is the same argument as the one about the liver's broad enzymes. In a 2011 review, Surh argued that the Keap1-Nrf2 pathway is the most important route by which dietary plant chemicals bring health benefits (Surh 2011).
If a comparison is wanted, this is more like a fire drill than a truckload of fire extinguishers. The drill is a nuisance, but afterwards the capacity to put out fires really is higher. The comparison stops there: in the real event there is no fire and no alarm, only an electron-poor carbon hitting a sulfur atom, and a bridge coming apart.
Chapter 5
Why the purified pill can backfire
The same molecule is a good thing when it comes from a vegetable. Purified, dosed up and put in a capsule, it can turn around and harm you.
The shape is a U
The sulforaphane mechanism carries this consequence with it. If the benefit comes from a little mild poison, then by that mechanism the link between dose and effect cannot be a line that keeps rising:
Too low a dose: the sensor is not touched, and nothing happens.The right dose: the sensor is touched, defenses are turned up, and the net result is good.Too high a dose: the electrophile no longer touches only KEAP1's row of cysteines. Cysteines are everywhere in the cell, and so is everything else it can bond to. At that point it is what it always was: a poison.
So there is a peak in the middle. What purifying and dosing up does is push you along the rising side and over the top. Eating vegetables, it is hard to get anywhere near the amount in one capsule.
And there is a second, subtler problem: high doses of antioxidants can also erase the very signal the body uses as an alarm.
The shape is a U
The sulforaphane mechanism carries this consequence with it. If the benefit comes from a little mild poison, then by that mechanism the link between dose and effect cannot be a line that keeps rising:
Too low a dose: the sensor is not touched, and nothing happens.The right dose: the sensor is touched, defenses are turned up, and the net result is good.Too high a dose: the electrophile no longer touches only KEAP1's row of cysteines. Cysteines are everywhere in the cell, and so is everything else it can bond to. At that point it is what it always was: a poison.
So there is a peak in the middle. What purifying and dosing up does is push you along the rising side and over the top. Eating vegetables, it is hard to get anywhere near the amount in one capsule.
And there is a second, subtler problem: high doses of antioxidants can also erase the very signal the body uses as an alarm.
Evidence · The trial that erased the signal
The Ristow 2009 trial makes this plain. Thirty-nine healthy young men (19 who had not been training, 20 who already trained) did 4 weeks of exercise; some of them also took 1000 mg of vitamin C and 400 of vitamin E a day, and the rest did not.The result: the improvement in insulin sensitivity appeared only in those not taking antioxidants.
Worse is what follows. Exercise normally prompts the body to build more of its own defenses against reactive oxygen (superoxide dismutases 1 and 2, and glutathione peroxidase); with antioxidant supplements, that response was blocked too (Ristow 2009).
Look carefully at what happened. The reactive oxygen made in exercising muscle is not only damage; it is also a signal. The body reads it and learns to raise its defenses and its metabolic capacity. Swallow high-dose antioxidants, neutralize the signal before it lands, and the body never gets the message, so it never adjusts.
You took out the alarm. The room looks clean, but the fire brigade never got the call.
Keep its limits in mind: this was a small, short trial that measured insulin sensitivity and gene activity, not disease outcomes. It is the mirror image of the sulforaphane mechanism: there, a little stress turns defenses up; here, a big dose flattens the stress, so defenses never turn up at all.
Evidence · Why beta-carotene harmed smokers
The beta-carotene affair, stated preciselyThe most famous reversal usually gets waved through in one sentence: antioxidants turned out to cause cancer. That sentence is lazy. The mechanism that can explain it needs three conditions at once.
Start with the chemistry. In 1984 Burton and Ingold found that beta-carotene is an antioxidant that depends on the oxygen pressure around it. Only at oxygen pressures well below 150 torr, the pressure of oxygen in normal air, is it a good trap for free radicals. At higher oxygen pressures it not only loses its antioxidant activity but turns into a self-feeding pro-oxidant, especially at relatively high concentrations (Burton 1984).
Most tissues in the body sit at the low end of that range, which is why it behaves itself as an antioxidant under ordinary conditions.
But a smoker's lung is not at the low end. It is among the highest-oxygen places in the body, and it is flooded with oxidants from smoke.
So the three conditions line up:
Purified: stripped of the hundreds of molecules that come with it inside a carrot.High dose: far beyond what anyone eats from vegetables.A specific environment: that lung, with high oxygen pressure plus the oxidants in smoke.
Hence the two trials that were stopped early. In ATBC (1994, male smokers, 20 mg of beta-carotene a day), lung cancers rose about 18% among those taking beta-carotene (ATBC 1994). In CARET (Omenn 1996, beta-carotene plus retinol, in smokers and asbestos-exposed workers), lung cancers rose about 28% (Omenn 1996).
Here is the part that must be exact: one word, hormesis (small doses help, large doses harm), does not explain this. Slapping a U-curve on it and calling it done uses a handsome word to cover three specific conditions. The three together are the most sensible explanation of these two trials so far, but they are pieced together from chemistry and trial results rather than proven inside the trials; remove any one and the conclusion might change.
Myth · Three trials fused into one
Don't fuse three trials into oneWhile we are here, separate a common confusion; these are often treated as one event:
ATBC (1994): vitamin E and beta-carotene in male smokers; the rise of about 18% in lung cancer appeared among those taking beta-carotene.CARET (Omenn 1996): beta-carotene plus retinol in smokers and asbestos-exposed workers; lung cancer rose about 28%.SELECT (Klein 2011): selenium and vitamin E in healthy men; in the group taking vitamin E alone (400 a day), prostate cancer rose about 17%. Not beta-carotene, not smokers, not the lung.
The three point to one lesson: purified high-dose antioxidants are not free. But their mechanisms cannot be borrowed from one another. The vitamin E in SELECT does not travel beta-carotene's oxygen-pressure road.
And one number, retired
The antioxidant capacity score once printed on packaging (ORAC) had its whole database withdrawn by the US Department of Agriculture in 2012. The reason given is direct: antioxidant capacity measured in a test tube does not predict health effects in the body (USDA 2012).
Why it cannot predict them, the sulforaphane mechanism has already answered. What matters was never how many free radicals the molecule traps in a test tube; it is whether it can reach KEAP1's row of cysteines inside your cells. Those are entirely different things, and a molecule can be excellent at the first while being incapable of the second.
Chapter 6
How to think about the unknown
"What nutrients does this food have?" is the wrong question.
It assumes the answer sits on a panel, and that panel was sieved by whether lacking something goes wrong within weeks. Most of what you want to know is not on this side of the sieve.
So what should you ask? Two things:
Does this bite bring enough different kinds of unfamiliar molecules?Does any one of them arrive faster than I can clear it?
Both questions land on something concrete in the body. The first lands on KEAP1's row of cysteines: something has to come along and touch it. The second lands on the capacity of the liver's production line, P450 plus the second step: the touch should not be too hard.
So what you can take away is not a list of what to eat (nobody has that list) but three judgments:
Variety beats betting on one thingWhole food beats the purified capsuleWhen you see the word unknown, ask whether it is being used to scare you or to sell to you
It assumes the answer sits on a panel, and that panel was sieved by whether lacking something goes wrong within weeks. Most of what you want to know is not on this side of the sieve.
So what should you ask? Two things:
Does this bite bring enough different kinds of unfamiliar molecules?Does any one of them arrive faster than I can clear it?
Both questions land on something concrete in the body. The first lands on KEAP1's row of cysteines: something has to come along and touch it. The second lands on the capacity of the liver's production line, P450 plus the second step: the touch should not be too hard.
So what you can take away is not a list of what to eat (nobody has that list) but three judgments:
Variety beats betting on one thingWhole food beats the purified capsuleWhen you see the word unknown, ask whether it is being used to scare you or to sell to you
Background · How this fits the food-additives story
Food Additives & the Zero-Added Label says that the body reads only three things: which molecule, how much, and what it arrived with; and once the clearance line is saturated, the link between dose and harm turns from a slope into a sharp bend.This story adds a premise to those three: the list of which molecule is far longer than you think, and you do not hold the full copy.
Put the two together and the conclusion changes shape. Since you know neither the complete list nor how to work out each dose, the strategy cannot be to assess molecules one by one. Only two rules remain:
Keep that infrastructure built for unknown molecules busy, and busy with variety.Don't let any single molecule sit at the capacity limit for long.
Myth · Unknown means dangerous
Not knowing gets used by two camps in opposite directions. Neither holds.The first camp's instinct is natural: most of these molecules were never studied, so avoid them and pick the product with the shortest ingredient list.
But the idea defeats itself. Among those hundred-odd thousand untracked molecules, the most vicious are precisely the natural ones: tetrodotoxin and aflatoxin were both made by living things to kill other living things. Meanwhile you successfully process a pile of unstudied plant molecules every single day, using exactly the liver's P450 enzymes and its second step. Your liver was built for this, and it manages it every day.
So fearing the unknown means fearing something you succeed at daily. If you must rank by danger, be wary of mold and natural toxins, not the long chemical names of legal additives. That ranking is exactly upside down.
Myth · Unknown means miraculous
The second camp costs more. The whole superfood pitch is built on it: since science tracks only a fraction, my as-yet-undiscovered miracle ingredient cannot be proven wrong.The sulforaphane example supplies the test. For a molecule to act on you, it has to actually touch something in your body: hit a cysteine, wedge into a pocket, block a gate. No contact, nothing happens.
And the argument treats every plant the same. Tens of thousands of unknown molecules are not one berry's selling point; they are every plant's default setup, including the cheapest cabbage at the market. Anyone selling that as exclusive is charging you for a universal fact.
In practice · Three judgments to take away
Three judgments to take away:Variety beats betting. You don't know the list, so you cannot pick the winner. Rotating what you eat is admitting that you don't know, and that is the only honest response.Whole food beats the purified capsule. The reason is that U-shape: purifying and dosing up is the fastest way to push someone over the peak.When you see the word unknown, ask whether it is being used to frighten you or to sell to you. Both exploit the same fact, and that fact says only that your body was ready for it long ago.
Know what is so, and know why. This story's why is an unusual one: the infrastructure you carry for the unknown, simply by existing, tells you that food is far more than what is on the label. You don't need to know those molecules. You only need to know that your body has been handling them for you all along.
Red flag · One thing for people on medication
This story is about mechanism. It is not medical advice and does not replace a doctor's judgment.One thing if you take medication
As described earlier, P450 enzymes can be induced: use them more and the body builds more. They can also be held down.
And what holds them down is often a plant. Grapefruit is the best-known case: a class of molecules in it inactivates in the wall of the small intestine, so the share of a drug that should have been broken down before reaching the blood is not, and the same tablet can put considerably more drug into the bloodstream (Bailey 2013). Dozens of medicines are affected, from cholesterol-lowering drugs to some blood-pressure drugs and immunosuppressants.
The lesson runs in two directions:
It confirms this whole story: your medicine and the plant's secondary metabolites are competing for the same production line. The body cannot tell which is a drug and which is a fruit; it reads only molecules.It also warns that eating more plants is not a cost-free move for someone on medication. If you want to change what you eat, ask a doctor or pharmacist rather than experimenting on your own.
Don't handle these yourself — see a doctor
Unexplained weight lossPersistent fatigue with pallorBlack or bloody stools, or food sticking when you swallowRecurrent fever or night sweats
One more deserves its own line: a rash, swelling of the lips or tongue, or difficulty breathing after eating something. That is what an acute allergic reaction looks like, and it needs immediate care rather than watchful waiting.
bailey-2013-grapefruit-drug
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