What nutrients actually do, one step at a time.

Small molecule

3,3'-Diindolylmethane / DIM

DIM is a dietary indole compound formed from indole-3-carbinol. Its receptor, enzyme, hormone and drug effects depend on dose, timing, tissue and formulation. Laboratory induction does not prove a clinical interaction with every CYP substrate; reduced tamoxifen metabolites have been measured in a randomized trial. DIM is not an established essential nutrient.

Chemical species

Acetic acid

Acetic acid, the ingested dietary acid, as supplied by vinegar. This entity is the exposure that is swallowed and is deliberately distinct from acetate, the circulating anion, which in this ledger also arrives from gut fermentation of fibre, from gut fermentation of fructose, and from hepatic alcohol metabolism. The two are not linked as a family; the step from ingestion to plasma acetate is recorded as its own claim. Species, exposure and limitations are retained in each linked claim.

Small molecule

Agmatine Sulfate

Sulfate salt of agmatine; PubChem CID 2794990, 1:1 composition, molecular formula C5H16N4O4S and molecular weight 228.27 g/mol. Salt mass is not free-agmatine mass. Not an established essential nutrient.

Small molecule

Aspartame

Context-specific entity; species, compartment and exposure are stated on each claim.

Drug

Aspirin / acetylsalicylic acid

Acetylsalicylic acid. Unlike other non-steroidal anti-inflammatory drugs it does not merely compete for the cyclooxygenase channel but transfers its acetyl group to the active-site serine, Ser530 in cyclooxygenase-1 and Ser516 in cyclooxygenase-2, which inactivates the first enzyme and converts the second into a catalyst that makes 15R products the native enzyme never makes. It is recorded here as an entity distinct from salicylate, the metabolite it becomes within minutes, because the two do not share a mechanism: salicylate does not acetylate, it competes with aspirin for the same site, and it has targets aspirin reaches only at high dose. Experimental model, exposure and limitations remain on each linked record.

Small molecule

Astaxanthin

Context-specific entity; species, compartment and exposure are stated on each claim.

Small molecule

Atorvastatin

Atorvastatin. Species, exposure and limitations are retained in each linked claim.

Small molecule

Berberine

Berberine is a plant protoberberine isoquinoline alkaloid studied as a pharmacological exposure, not an essential nutrient. Salt, formulation, dose, species, time and tissue are retained in claims. Human CYP inhibition and cyclosporine interactions are measured; many proposed metabolic benefits remain preclinical or population-specific.

Chemical species

Beta-glucan

Beta-glucan. A family of glucose polymers defined by their linkage pattern rather than a single compound; the preparations in this collection differ in backbone, branching, molecular weight, conformation, solubility, particle size and purity, and each is recorded as its own entity with no family link joining them, because those differences determine which receptor engages and whether engagement signals at all. Species, exposure and limitations are retained in each linked claim.

Small molecule

Betalains

A family of nitrogen-containing dietary plant pigments, including betacyanins and betaxanthins. This collection separates betanin, betanidin, indicaxanthin, vulgaxanthin I and neobetanin. It covers lipid oxidation, vitamin E preservation, myeloperoxidase/chloride chemistry, Nrf2 responses, intestinal inflammatory signaling and red-cell death pathways. Nonessential phytochemicals: no established human deficiency syndrome. Cell assays, isolated proteins and human food-exposure studies remain distinct; betalains are neither betaine nor dietary nitrate.

Small molecule

Biotin

Vitamin B7; substrate for multivitamin transport and cofactor precursor for carboxylases.

Nutrient element

Boron

Element boron and dietary boron as a research topic. Human essentiality, a required intake and a specific human deficiency syndrome have not been established. Chemical forms, species and exposure conditions are distinguished in individual claims.

Peptide

Bromelain

A compositionally variable mixture of cysteine proteases and associated pineapple-stem proteins; activity units and preparation matter. It is not one pure enzyme.

Small molecule

Butyrate

Butyrate. Species, exposure and limitations are retained in each linked claim.

Small molecule

Caffeine

Caffeine. Species, exposure and limitations are retained in each linked claim.

Nutrient element

Calcium

Nutritional calcium element; distinct from free Ca2+, salts, mineral deposits and calcium-signaling events. Nutritional element; not elemental metal exposure, free calcium ion, or a specific calcium salt. Forms and intake are recorded in each event.

Small molecule

Capsaicin

Species, assay, exposure and limitations are retained on linked claims.

Chemical species

Ceylon cinnamon / Cinnamomum verum bark preparations

Ceylon cinnamon / Cinnamomum verum bark preparations. Species, exposure and limitations are retained in each linked claim.

Nutrient element

Chloride

Chloride nutrient topic. The independently modeled chemical species is chloride ion (Cl−). Dietary shortage, gastrointestinal or renal losses, blood concentration, intracellular gradients and genetic transport defects are different states. Sodium chloride, potassium chloride and chloride-rich intravenous fluids retain their accompanying ions and routes.

Small molecule

Chlorogenic acid / 5-O-caffeoylquinic acid

Chlorogenic acid, 5-O-caffeoylquinic acid under the quinic-acid numbering convention used in the linked analytical study; CAS 327-97-9. Historical 3-CQA naming must be resolved by structure/convention. Plural chlorogenic acids, coffee extracts and metabolites are not this single molecule. No essential dietary requirement or deficiency syndrome is established.

Small molecule

Choline

Independent biological entity. Read linked claims for experimental scope and context.

Nutrient element

Chromium

Chromium research collection. Nutritional chromium(III), individual supplement compounds and toxic chromium(VI) are distinct exposures. Human essentiality remains disputed; there is no validated general chromium-status test or established dietary deficiency syndrome. Historical parenteral case reports and experimental low-intake studies retain their specific scope.

Chemical species

Coenzyme Q10 / CoQ10 redox system

Coenzyme Q10 is an endogenously synthesized lipid redox carrier. Oxidized ubiquinone-10 and reduced ubiquinol-10 support electron transfer and membrane protection; their location, regeneration and availability matter.

Drug

Cold water immersion

Cold water immersion. Species, exposure and limitations are retained in each linked claim.

Chemical species

Conjugated linoleic acid / CLA isomer family

CLA is a family of fatty-acid isomers. This chapter keeps cis-9,trans-11, trans-10,cis-12 and mixed preparations separate while tracing fat-cell signaling, vitamin A transport, calcium, omega-3 interactions, nitrite chemistry and human trial outcomes. Plain explanations accompany full technical records and exact sources.

Nutrient element

Copper

Copper; read each linked claim for the measured context and model.

Small molecule

Coumarin

Coumarin. Species, exposure and limitations are retained in each linked claim.

Small molecule

Creatine

Independently recorded entity or measured process. Linked claims specify compartment, assay and experimental scope.

Chemical species

Cucurbitacins

Context-specific entity; species, compartment and exposure are stated on each claim.

Small molecule

Curcumin

Curcumin (diferuloylmethane; CAS 458-37-7) is one turmeric-derived diarylheptanoid polyphenol. It is distinct from turmeric, mixed curcuminoid extracts, absorption-enhanced products, conjugates and reduced or oxidized metabolites. Its chemical reactivity and exposure depend on preparation and assay. No essential dietary requirement or specific human curcumin-deficiency syndrome is established.

Drug

Cyclosporine

Species, preparation, dose and limitations are retained on linked claims.

Small molecule

D-Aspartate

Context-specific entity; species, compartment and exposure are stated on each claim.

Drug

Delta-9-tetrahydrocannabinol / THC

Delta-9-tetrahydrocannabinol / THC. Species, exposure and limitations are retained in each linked claim.

Small molecule

Dietary (3R,3-prime-R)-zeaxanthin

Dietary (3R,3-prime-R)-zeaxanthin. Species, exposure and limitations are retained in each linked claim.

Small molecule

Dihydrocapsaicin

Dihydrocapsaicin, the second most abundant capsaicinoid of chilli, differing from capsaicin by a single double bond in its side chain. It is recorded here as an entity distinct from capsaicin and is not linked to it as a family, because capsaicin holds its own chapter and because studies that measured the two head to head found them equal on nerve conduction block, about 65% apart on hypothermia, divergent on platelet aggregation and fivefold apart on endothelial cytotoxicity. Those comparisons are recorded as their own claims. Species, exposure and limitations are retained in each linked claim.

Small molecule

Epigallocatechin-3-gallate (EGCG)

The (-)-epigallocatechin-3-gallate compound; distinct from whole green tea, mixed extracts and its conjugated metabolites.

Drug

Ethanol

Ethanol. Species, exposure and limitations are retained in each linked claim.

Small molecule

Eugenol

A phenylpropene found in clove oil and other plants. Purified eugenol, clove oil, inhaled flavor mixtures and thermal products are distinct exposures.

Cellular process

Fasting / abstention from energy intake

Fasting is a physiological state: the body shifts fuel use, keeps making glucose, produces and uses ketones, and changes hormone and nutrient-sensing signals. This chapter connects those steps to specific enzymes and nutrient dependencies, including magnesium, thiamine, riboflavin, niacin, biotin, choline and copper. Human fasting, cell-starvation experiments and refeeding retain their distinct settings. Open the preserved fasting source for the full readable pathway overview and discovery questions.

Small molecule

Fisetin

Fisetin is a plant flavonol with effects that depend on concentration, cell state and metabolism. This collection connects glutathione regulation, iron and copper chemistry, GPX4-dependent lipid protection, senescence, nutrient-sensing kinases and drug metabolism. Fisetin, geraldol and conjugates remain separate entities. Human trials, chemical reactions, cell experiments and animal outcomes retain their own evidence limits; reduced senescence markers do not automatically mean senescent-cell killing.

Chemical species

Folate (vitamin B9)

Folate is a family of compounds that carry one-carbon units for nucleotide synthesis and connected methylation reactions. Folic acid, reduced folates and their cellular forms remain independently identified. Nutrient family, distinct from folic acid and individual reduced folate forms.

Chemical species

Fulvic acid (heterogeneous humic fraction)

Operational heterogeneous humic fraction, not a single molecular structure or established essential nutrient. Individual preparations and the distinct fungal molecule CAS 479-66-3 are recorded separately.

Small molecule

Gamma-aminobutyric acid

Gamma-aminobutyric acid. A four-carbon amino acid that acts as a signalling molecule rather than by any chemistry of its own, and that carries no intrinsic direction: it opens a chloride channel, and whether the cell is quietened or excited is set by the chloride gradient across the membrane, which belongs to the transporters. Inducing the exporter KCC2 during neuronal maturation flips the response from depolarising to hyperpolarising, knocking KCC2 down flips it back in a mature neuron, and after peripheral nerve injury the same receptor makes normally inhibitory currents excitatory in the spinal dorsal horn. It is made in one step by glutamate decarboxylase using pyridoxal 5-phosphate, and at least half the brain enzyme sits as apoenzyme without bound cofactor as a reserve for sudden demand, which is why two unrelated inherited disorders that remove usable cofactor both present with pyridoxine-responsive seizures. Outside the brain it is a paracrine signal in the pancreatic islet, where it is released with insulin and suppresses glucagon, and it is made and sensed by immune cells, in which its effect reverses with the setting: protective in autoimmune models, host-protective in intracellular bacterial infection, and harmful in tumours, where B cell-derived GABA drives monocytes toward interleukin-10-secreting macrophages that suppress CD8 killing. Taken by mouth its access to the brain is limited: the blood-brain barrier carries it with a Michaelis constant of 679 micromolar, the brain exports it back to blood, and systemic infusion across a thousand-fold dose range raised cerebrospinal fluid GABA only to about 11 micromolar. Species, cell type and the measured gradient are retained in each linked claim.

Small molecule

Gamma-nonalactone

C9H16O2; CAS 104-61-0; nonan-4-olide / 5-pentyloxolan-2-one. Flavor and fragrance lactone, not an established essential nutrient or therapy. Generic records do not resolve enantiomer composition unless stated; FDA GSRS registers CAS 104-61-0 as racemic. Distinct from delta-nonalactone, gamma-decalactone, gamma-butyrolactone and GHB. Identity: https://precision.fda.gov/ginas/app/ui/substances/99a11123-4b6b-41c5-b472-a70449e3a6b4

Small molecule

Gingerols

Dietary phenolic compounds of ginger, including 6-, 8- and 10-gingerol. This collection separates purified gingerols, the dehydration product 6-shogaol, position-specific glucuronides and whole-ginger preparations. It covers TRPV1, 5-HT3 signaling, calcium/AMPK/glucose uptake, airway beta-agonist responses, neutrophil PDE/cAMP/PKA signaling and metabolism. Nonessential phytochemicals with no established human deficiency syndrome; laboratory effects are not a dosing recommendation.

Small molecule

Glycine

Independent small molecule record; interpretation is limited by each linked claim and its study context.

Botanical

Graviola / Annona muricata

Annona muricata (soursop/graviola), a botanical whose fruit, juice, leaves, seeds, teas and extracts have different compositions. Whole-plant effects are not interchangeable with purified annonacin.

Small molecule

GSH

Reducing cosubstrate in glutathione peroxidase assays.

Small molecule

Hericenones and erinacines

A navigation family joining structurally distinct hericenones and erinacines from Hericium erinaceus. Family membership does not transfer one member's effect to another.

Chemical species

High-Fructose Corn Syrup / HFCS

A corn-derived glucose-fructose sweetener mixture, not one molecule and not pure fructose. HFCS-42 and HFCS-55 are separate formulations. Component-only experiments do not establish an HFCS-specific effect or a unique risk relative to sucrose.

Protein state

Human ZDHHC7 knockout in HEK293T

Small molecule

Hydroxytyrosol

3,4-Dihydroxyphenylethanol, an olive phenol also formed endogenously from tyrosol. Free compound, conjugates and olive-food matrices are distinct exposures.

Drug

Hyperbaric oxygen therapy

Hyperbaric oxygen therapy. Species, exposure and limitations are retained in each linked claim.

Drug

Ibuprofen

A 2-arylpropionic acid non-steroidal anti-inflammatory drug, sold and swallowed as a racemate. Unlike aspirin it inhibits cyclooxygenase reversibly and competitively rather than by acetylating it. The racemate is recorded here as an entity distinct from each of its two enantiomers, which are not linked to it or to each other as a family: only S(+)-ibuprofen inhibits cyclooxygenase-1, by 32 to 96 fold depending on the readout, while at cyclooxygenase-2 the two are indistinguishable; only R(-)-ibuprofen is activated to a coenzyme A thioester, which is what drives the one-way inversion of R to S and what gets R esterified into body triacylglycerol; and the two are cleared by different cytochromes. Context-specific entity; species, compartment and exposure are stated on each claim.

Small molecule

Indicaxanthin

Yellow betaxanthin found in cactus pear. Its responses must not be generalized to every betalain.

Chemical species

Inositol (stereoisomer family)

Inositol is a family of ring-shaped sugar alcohols. The body can make myo-inositol, which supplies membrane lipids and signaling molecules that connect calcium release, ion channels, phosphate handling and protein anchoring. Free inositol, its stereoisomers, and phosphorylated derivatives have different actions; clinical effects depend on the form, tissue and study context.

Nutrient element

Iodine

Independent biological entity. Read linked claims for experimental scope and context.

Nutrient element

Iron

Elemental nutrient category; chemical oxidation state must be specified separately when measured.

Drug

Ivermectin

Semi-synthetic macrocyclic lactone derived from avermectin B1a. Species, preparation, concentration and limitations are retained on linked claims.

Small molecule

L-Alanine

Amino acid product of SCLY-catalyzed selenocysteine decomposition.

Small molecule

L-Arginine

Independent small molecule record; interpretation is limited by each linked claim and its study context.

Small molecule

L-Aspartate

L-Aspartate

Small molecule

L-Carnitine

Independent small molecule record; interpretation is limited by each linked claim and its study context.

Small molecule

L-Carnosine / beta-alanyl-L-histidine

Carnosine links beta-alanine and histidine supply to muscle chemistry, calcium handling, reactive-aldehyde trapping and peptide transport. Explore its connections with magnesium-ATP, manganese, zinc, glutathione, vitamin C and methyl donors, with human findings separated from cell and animal experiments.

Small molecule

L-Citrulline

L-Citrulline is a non-proteinogenic amino acid made in the body. It participates in nitrogen disposal and supplies arginine through ASS1 and ASL. Low blood citrulline, impaired conversion and dietary intake are distinct; each mechanism retains its experimental scope.

Small molecule

L-Cysteine

L-Cysteine Independently recorded entity or measured process. Linked claims specify compartment, assay and experimental scope.

Small molecule

L-Ergothioneine

Ergothioneine is a food-derived, sulfur-containing histidine derivative whose cellular availability depends on transport. This collection connects SLC22A4 and SLC22A15 uptake to sodium, carnosine, carnitine and thiamine; redox chemistry to vitamin C, glutathione and copper; and microbial synthesis to histidine, SAM, cysteine, iron and PLP. It also records vascular, immune, mitochondrial, microbial and brain mechanisms. Human uptake, dialysis depletion, preliminary clinical findings and animal experiments retain separate evidence labels. Shared pathways support discovery questions without proving supplement synergy or a human deficiency threshold.

Small molecule

L-Glutamate

Independent small molecule record; interpretation is limited by each linked claim and its study context.

Small molecule

L-Histidine

L-Histidine

Small molecule

L-Isoleucine

Branched-chain essential amino acid.

Small molecule

L-Lysine

Free L-enantiomer of lysine, an indispensable proteinogenic amino acid. Separate from protein-bound lysine residues, D-lysine and polylysine.

Small molecule

L-Methionine

Free sulfur-containing essential amino acid; distinct from protein-bound methionine.

Small molecule

L-Phenylalanine

Context-specific entity; species, compartment and exposure are stated on each claim.

Small molecule

L-Proline

Study-scoped entity; inspect species, exposure and experimental limitations on each claim.

Small molecule

L-Serine

L-Serine Independently recorded entity or measured process. Linked claims specify compartment, assay and experimental scope.

Small molecule

L-Theanine

L-Theanine is a non-protein amino acid found in tea. Human absorption, selected stress/sleep/attention outcomes and laboratory transport/signaling mechanisms are recorded separately. It is not an established essential nutrient and has no established dietary deficiency syndrome. Mixed-product results are not assigned to theanine alone.

Small molecule

L-Threonine

Context-specific entity; species, compartment and exposure are stated on each claim.

Small molecule

L-Tryptophan

L-Tryptophan

Small molecule

L-Tyrosine

L-Tyrosine. Species, exposure and limitations are retained in each linked claim.

Small molecule

Lariciresinol, enantiomer unresolved

Aglycone recorded where the report does not state which enantiomer was used.

Small molecule

Lipoic acid

Lipoic acid

Nutrient element

Lithium

Lithium is an element whose biological chemistry involves Li+ ions. Food and water supply trace amounts; prescription treatment produces a very different exposure. Lithium carbonate, chloride and orotate remain separate records. A salt's mass is not its elemental lithium mass, and a cell-culture concentration is not an oral dose. Magnesium connects two central branches: lithium can interfere with metal-dependent enzymes, including GSK3 and inositol phosphatases. Inositol recycling changes cell signaling and, in some experiments, protein recycling by autophagy. These observations do not show that lithium strips magnesium from the body or that magnesium supplements predictably reverse its effects. The kidney provides a second network. Sodium channels help lithium enter collecting-duct cells; water-channel changes can impair urine concentration. Sodium intake, sodium loss, fluid loss and interacting medicines change lithium handling. Potassium-deprivation records converge on AQP2 water channels, but that shared target alone does not establish a combined effect. Calcium/PTH regulation and thyroid hormone release provide additional endocrine connections, including the existing potassium-iodide interaction record. Beyond these familiar pathways, the collection connects lithium to PAP clearance and sulfation, cartilage and brain extracellular matrix, citrate transport and lipid synthesis, glycogen storage, neuronal survival, glutamate uptake and circadian clocks. Transporter responses can reverse between species: human and rodent SLC13A5 must not be merged into one supposedly universal effect. The 2025 brain study separates human tissue associations from experimental dietary depletion in mice and lithium-orotate rescue in mouse models. It does not establish a human dietary deficiency threshold or a treatment for dementia. Human cognitive trials retain positive and null findings: the 2026 pilot met none of its six prespecified primary significance thresholds. Differences in exposure, population and outcomes remain visible rather than being turned into a claim of proven prevention. The graph supports discovery questions, not automatic conclusions about synergy or disease causation. Mechanistic records remain source-derived drafts with exact curation spans, primary references and experimental limits. This is a substantial collection, not a claim to capture every possible lithium mechanism.

Small molecule

Lutein

Lutein. Species, exposure and limitations are retained in each linked claim.

Small molecule

Luteolin / 3′,4′,5,7-tetrahydroxyflavone

Luteolin is a plant flavone, distinct from lutein. Explore its conjugated metabolites, gut microbial conversion, immune and platelet signaling, and connections to SAM/magnesium, NAD, iron/copper and glutathione defenses. Most target effects were measured in enzymes, cells or animals. The availability scenarios describe altered transport or molecular machinery; they do not establish a luteolin-deficiency syndrome.

Small molecule

Lycopene

Lycopene. Species, exposure and limitations are retained in each linked claim.

Nutrient element

Magnesium

Nutritional magnesium element; distinct from free Mg2+, salts and Mg-nucleotide complexes. Nutrient element magnesium; dietary supply is distinct from serum concentration, free intracellular Mg2+, and Mg-bound metabolites. The dietary nutrient element magnesium; distinct from free Mg2+ and Mg-nucleotide complexes. Nutritional magnesium element; distinguish intake, ionized pools, salts and Mg-nucleotide complexes.

Nutrient element

Manganese

Dietary manganese; distinct from its divalent ion and transporter-dependent cellular uptake.

Small molecule

Mangiferin

Mangiferin is a C-glucosyl xanthone (CAS 4773-96-0), distinct from mango fruit, bark or leaf extracts, its monosodium formulation, and the aglycone norathyriol. Preparation, microbial conversion, concentration and tissue determine the scope of each recorded finding. No essential dietary requirement or specific mangiferin-deficiency syndrome is established.

Drug

Mebendazole

Mebendazole. A benzimidazole carbamate anthelmintic introduced for human use in 1971; it is recorded as an entity distinct from albendazole, from the wider benzimidazole class and from its own crystal forms, because albendazole acts partly through a sulfoxide metabolite mebendazole does not form, because the class members differ by orders of magnitude in potency, and because polymorph A is therapeutically inert where polymorph C is active. Species, exposure and limitations are retained in each linked claim.

Small molecule

Melatonin

Melatonin. Species, exposure and limitations are retained in each linked claim.

Drug

Metformin

Metformin Independent substance, clinical endpoint or measured readout; study context is retained with each finding.

Nutrient element

Molybdenum

Molybdenum. Species, exposure and limitations are retained in each linked claim.

Small molecule

Monosodium L-glutamate

Context-specific entity; species, compartment and exposure are stated on each claim.

Botanical

Moringa oleifera

Moringa oleifera is a botanical food and supplement. Fresh or dried leaf, leaf powder, tea, hydroethanolic extract, seed extract, glucomoringin and purified moringin are compositionally distinct actors.

Small molecule

Myricetin

Myricetin is a plant flavonol, distinct from myricitrin and dihydromyricetin. Explore its sulfate and microbial metabolites, selenium-dependent thioredoxin machinery, glutathione, copper, vitamin E, calcium, purine oxidation and melatonin links. Enzyme, cell and animal experiments retain their limits. The APE1 disagreement has its own discussion page. No human myricetin-deficiency syndrome is established.

Small molecule

NAD+

Metabolic dinucleotide substrate of the reported SELENOO hydrolysis reaction.

Small molecule

Naringenin

A citrus flavanone aglycone. Naringin is a separate glycoside precursor; circulating sulfate and glucuronide conjugates are separate chemical species.

Small molecule

Nasunin

Nasunin is an acylated delphinidin anthocyanin found in some eggplant peels. Cis and trans isomers, purified pigment and mixed extracts are recorded separately. Evidence covers iron chemistry, redox responses and preclinical signaling; no essential-nutrient requirement or nasunin-deficiency syndrome is established.

Peptide

Nattokinase / subtilisin NAT

The purified mature 275-residue bacterial subtilisin-family serine protease of Bacillus subtilis var. natto, sequence-derived mass 27,728 Da, EC 3.4.21.62. This entity is the purified enzyme only. Natto the food, the crude fermentation powder, the NSK-SD product and a generic supplement are separate entities in this chapter because they differ in composition in ways that change the answer to a clinical question.

Nutrient element

Niacin (vitamin B3)

Vitamin B3 nutritional family, including nicotinic acid and nicotinamide. Precursor forms, NAD+/NADH and NADP+/NADPH have separate identities; chemical form and experimental exposure determine each claim.

Small molecule

Pantothenate (vitamin B5)

Vitamin precursor of the pantetheine moiety of coenzyme A.

Drug

Paracetamol

Paracetamol, also called acetaminophen. An analgesic and antipyretic that is only weakly anti-inflammatory, does not inhibit platelet function and does not injure the gastric mucosa, and is a weak inhibitor of both cyclooxygenases in isolated enzyme preparations. Its mechanism remains contested: it acts as a reducing cosubstrate at the peroxidase site so that its potency falls as ambient hydroperoxide rises, which would account for the tissue pattern; a proposed third cyclooxygenase does not translate beyond the dog; and in rodents it is deacetylated and conjugated with arachidonic acid to AM404, which carries the analgesia but not the effect on body temperature. It is recorded as an entity distinct from NAPQI, the metabolite that causes the liver injury, and from AM404, and is not linked to either as a family. Species, exposure and limitations are retained in each linked claim.

Chemical species

Pectin, structurally heterogeneous plant polysaccharides

Pectin is a family of structurally heterogeneous plant cell-wall polysaccharides, not one small molecule. Homogalacturonan, RG-I, RG-II and side chains have separate identities. Methylesterification, its distribution, molecular size, source and processing affect behavior. No essential pectin intake or specific human pectin-deficiency syndrome is established. Modified citrus products are not interchangeable with food pectin.

Small molecule

Phlorizin

Phloretin 2'-O-glucoside, also spelled phloridzin or phlorhizin. Parent glycoside, phloretin aglycone and conjugated metabolites are distinct actors.

Nutrient element

Phosphorus

Phosphorus. Species, exposure and limitations are retained in each linked claim.

Nutrient element

Potassium

Nutrient element potassium; dietary intake and body balance are distinct from free potassium ions or a serum measurement.

Chemical species

Potassium iodide

Potassium salt used to administer iodide; study doses are iodine mass, not whole-salt mass, where stated.

Chemical species

Red yeast rice

Context-specific entity; species, compartment and exposure are stated on each claim.

Small molecule

Resveratrol

Context-specific entity; species, compartment and exposure are stated on each claim.

Small molecule

Riboflavin (vitamin B2)

Vitamin precursor of FMN and FAD.

Small molecule

S-allyl-L-cysteine / SAC

Context-specific entity; species, compartment and exposure are stated on each claim.

Nutrient element

Selenium

Elemental selenium considered as the upstream nutrient input.

Drug

Sildenafil

Sildenafil. A competitive inhibitor of phosphodiesterase type 5 that does not generate a signal but prevents one being cleared: it occupies the catalytic site with an inhibition constant of 1 nanomolar against a cyclic GMP Michaelis constant of 2000 nanomolar, so cyclic GMP made by guanylate cyclase in response to nitric oxide survives longer. Without nitric oxide drive it had no functional effect on isolated cavernosal tissue and did not raise intracavernosal pressure in the anaesthetised dog until the pelvic nerve was stimulated, though whether that requirement is absolute is recorded here as an open disagreement. Because organic nitrates raise the same messenger at a different point on the same pathway, the two potentiate rather than add, and a sublingual nitrate tablet produced a fourfold greater fall in systolic pressure. The target enzyme is present in cavernosal and vascular smooth muscle, platelets and the pulmonary arterial wall and is not detectable in human cardiac ventricle. Selectivity is 80 to 19,000-fold over PDE1 to PDE4 but only about tenfold over retinal PDE6, which is the basis of the visual effects. It is recorded as an entity distinct from its active N-desmethyl metabolite, and its target is recorded as distinct from PDE6, with neither pair linked as a family. Species, exposure and limitations are retained in each linked claim.

Chemical species

Silica and soluble silicon

A collection spanning soluble silicon chemistry and silica particles. Orthosilicic acid transport, connective-tissue responses and particle injury retain separate molecular identities, routes and experimental exposures.

Nutrient element

Sodium

Nutrient element sodium; dietary sodium restriction is distinct from distal luminal sodium delivery or serum sodium concentration.

Small molecule

Spermidine

Spermidine is a polyamine supplied by cellular synthesis, food and microbes. Explore NAD- and iron-dependent hypusination, amino-acid and SAM metabolism, transport, autophagy, immune cells, mitochondrial proteins and ion channels. Human trial results, failed rescues and experimental limitations are retained. No human dietary spermidine-deficiency threshold is established.

Small molecule

Stevia

Botanical sweetener collection from Stevia rebaudiana. A grouping of preparations, not one chemically pure molecule and not an essential nutrient. Individual glycosides and metabolites are separately identified.

Nutrient element

Strontium

Strontium interacts with calcium-sensitive transport, signaling and mineral chemistry. Stable strontium, drug formulations and laboratory exposures are distinguished; a response to strontium is not evidence of a nutritional requirement.

Small molecule

Sucrose

Context-specific entity; species, compartment and exposure are stated on each claim.

Small molecule

Sulforaphane / SFN, stereochemistry specified per study

Sulforaphane is a broccoli-derived isothiocyanate formed from glucoraphanin. Its exposure depends on myrosinase and microbial conversion; its effects involve electrophile sensing, glutathione metabolism and other targets. It is not an essential vitamin, and no sulforaphane-deficiency syndrome is established.

Drug

Tadalafil

Tadalafil. A long-acting competitive inhibitor of phosphodiesterase type 5, with a half-maximal inhibitory concentration of 5 nanomolar and high selectivity for PDE5 over PDE1 to PDE4 and over PDE6; the cis-(6R,12aR) piperazinedione enantiomer carries the potency reported in the discovery series. Like sildenafil it preserves cyclic GMP rather than producing it, and PDE5 carries the principal cyclic GMP hydrolysing activity in human corpus cavernosum, where the downstream relaxation requires cyclic GMP-dependent protein kinase I. What distinguishes it from sildenafil in this ledger is measured rather than asserted: 85-fold greater selectivity against the retinal PDE6, and a mean plasma half-life of 17.5 hours with 5th and 95th percentiles of 11.5 and 29.6 hours. The longer half-life is also the shape of the nitrate interaction, which persisted at 4, 8 and 24 hours and was no longer detectable at 48, 72 and 96 hours. Three endpoints are recorded in three conditions: a 2.3 point improvement in the International Prostate Symptom Score at 5 mg once daily, a 33 metre placebo-corrected increase in six-minute walk distance in pulmonary arterial hypertension where only the 40 mg dose met the prespecified significance level, and the structure of the human PDE5 catalytic domain solved with this drug bound. Its target is recorded as an entity distinct from the homologous retinal PDE6, with no family link joining them, because the selectivity ratio between them is what the comparison above measures. Species, exposure and limitations are retained in each linked claim.

Small molecule

Tartrazine

Synthetic azo colorant, E102 / FD&C Yellow No. 5; sodium salt CAS 1934-21-0. Not an essential nutrient or established therapeutic agent. Distinct from Sunset Yellow FCF / E110 and from its own reduction and oxidation products. Results from dye mixtures are not attributed to tartrazine alone.

Small molecule

Taurine

Taurine. Species, exposure and limitations are retained in each linked claim.

Small molecule

Thiamine (vitamin B1)

Unphosphorylated vitamin B1; substrate for TPK1.

Nutrient element

Vanadium

Vanadium chemistry connects phosphate-sensitive enzymes, ion pumps, redox reactions and metal-binding proteins. Oxidation state, ligand, dose and experimental model determine the response; drug-like effects do not establish a dietary requirement.

Chemical species

Vitamin A

Vitamin A is a family of nutrient activities involved in vision, gene regulation and tissue function. Retinol, retinal isomers, retinoic acid, retinyl esters and provitamin carotenoids have separate records because they perform different roles.

Chemical species

Vitamin B12 (cobalamins)

Nutrient family, distinct from individual cobalamin forms. Cobalamin nutrient family; distinct from individual coenzyme forms.

Chemical species

Vitamin B6

Vitamin B6 is a family of related compounds. Its active cofactor forms support amino-acid reactions, neurotransmitter synthesis, heme production and other pathways. Individual forms, deficiency, genetic impairment and excess exposure are recorded separately. Vitamin B6 vitamer family; pyridoxine, pyridoxal, pyridoxamine and their phosphorylated forms remain separate chemical entities.

Chemical species

Vitamin C

Vitamin C supports connective-tissue enzymes and selected cellular redox reactions. Absorption, recycling and enzyme availability connect it with other nutrients. Reduced ascorbate, ascorbic acid and oxidized dehydroascorbic acid are recorded separately. Independent measured endpoint or substance; model, assay and exposure are retained in each linked finding.

Chemical species

Vitamin D2 and D3

Two vitamin forms feed a regulated hormone system. Follow their activation, cellular responses, and links to calcium, phosphate and magnesium. D2, D3, their metabolites and blood measurements have separate records. Combined nutritional chapter covering ergocalciferol and cholecalciferol; chemically distinct metabolites remain separate.

Chemical species

Vitamin E

Vitamin E comprises related tocopherols and tocotrienols. Follow their transport, membrane protection, deficiency effects and nutrient interactions. Individual forms and experimental outcomes have separate records.

Chemical species

Vitamin K2 / menaquinone family

Vitamin K2 is a family of menaquinones, including MK-4 and MK-7. These forms participate in the shared vitamin K cycle but differ in synthesis, exposure and studied effects.

Nutrient element

Zinc

Independent biological entity. Read linked claims for experimental scope and context.