Antioxidants

Coenzym Q10 (Ubichinon)

2,3-dimethoxy-5-methyl-6-decaprenyl-1,4-benzoquinone

Coenzyme Q10 (CoQ10, ubiquinone) is a fat‑soluble, vitamin‑like compound central to mitochondrial energy production and antioxidant defense. Humans synthesize CoQ10 endogenously (via the mevalonate pathway); tissue levels decline with age and some drugs (notably statins). Supplementation (commonly 100–300 mg/day) has evidence supporting clinical benefits for heart failure, mitochondrial disease, migraine prevention, male fertility, and statin‑associated muscle symptoms, though results vary by formulation and dose. Ubiquinol (reduced form) shows higher oral bioavailability than ubiquinone (oxidized form). CoQ10 is generally well tolerated; common side effects are mild GI complaints (<5%). Important interactions include potential reduction of warfarin anticoagulant effect and altered statin‑induced CoQ10 depletion. No US RDA exists (NIH/ODS: no recommended daily intake); therapeutic dosing should be individualized and discussed with clinicians. This article provides an exhaustive, evidence‑based review including pharmacokinetics, mechanisms, clinical trial results, safety, drug interactions, product selection criteria for the US market, and practical dosing guidance.

Coenzym Q10 (Ubichinol)

Reduced form of Coenzyme Q10

Coenzyme Q10 in its reduced form, ubiquinol, is a lipid-soluble, mitochondrial electron carrier and membrane antioxidant that supports cellular energy production and protects lipids from peroxidation. Endogenously synthesized via the mevalonate pathway and obtained from small amounts in food, ubiquinol circulates on lipoproteins and concentrates in high-energy tissues such as heart, skeletal muscle, liver and kidney. Clinical uses supported by randomized trials and meta-analyses include adjunctive therapy in chronic heart failure, reduction of statin-associated myalgias (in some trials), improvement in sperm quality, and migraine prophylaxis; dosing typically ranges from 100–300 mg/day for ubiquinol supplements, taken with a fat-containing meal to maximize lymphatic absorption. Ubiquinol is generally well tolerated; drug interactions of clinical significance include potential INR reduction with warfarin and absorption interference with bile-acid sequestrants. This article is a comprehensive, evidence-focused encyclopedic guide for clinicians and informed consumers in the US market, covering chemistry, pharmacokinetics, mechanisms, clinical evidence, dosing, safety, interactions, product selection and regulatory context with NIH/FDA references and practical application guidance.

Glutathion (reduziert)

L-γ-glutamyl-L-cysteinyl-glycine

Glutathione (reduced, GSH) is a naturally occurring tripeptide antioxidant — <strong>the most abundant low‑molecular‑weight thiol in cells, typically present in the reduced form at >99% of total glutathione in healthy cells</strong>. This encyclopedia‑level guide synthesizes biochemical fundamentals, pharmacokinetics, clinical uses, formulation science and practical dosing strategies for the U.S. market. It explains why hepatic and mitochondrial pools are critical, how oral formulations are degraded by intestinal γ‑glutamyltranspeptidase (GGT), and why specialized forms (liposomal, S‑acetyl) or intravenous dosing are used to overcome bioavailability limits. The article summarizes mechanism (GPx, GST, GSR cycling), details eight evidence‑mapped clinical benefits with mechanistic context, lists common adverse events and drug interactions (notably platinum chemotherapies and acetaminophen management), and gives a U.S. consumer checklist for product quality (CoA, GMP, third‑party testing). Practical dosing recommendations, timing advice, and synergy combinations (NAC, whey, selenium, vitamins C/E) are provided to help clinicians and informed consumers choose safe, evidence‑based strategies. Sources include authoritative biochemical reviews and public databases (PubChem; NCBI Bookshelf).

Liposomales Glutathion

Liposome-encapsulated L-glutathione

Liposomal glutathione is an oral formulation that encapsulates reduced L‑glutathione (GSH) in phospholipid vesicles to protect the tripeptide from gastrointestinal degradation and enhance systemic delivery. Clinical and biochemical data suggest liposomal delivery may increase circulating and intracellular GSH markers versus plain oral GSH, with typical consumer doses of <strong>150–1,000 mg/day</strong> (commonly 250–500 mg/day). This premium encyclopedia article summarizes chemistry, pharmacokinetics, mechanisms, eight science‑backed benefits, dosing guidance, safety, drug interactions, selection criteria for US consumers, and research gaps — using consolidated biochemical principles and formulation data. Note: I used the supplied comprehensive research dossier as the primary source for all mechanistic and quantitative statements; to append live PubMed/DOI citations (2020–2026) please reply with permission for PubMed access and I will embed verifiable PMIDs/DOIs on request.

S-Acetyl-Glutathion

S-acetyl-L-glutathione

S-Acetyl Glutathione (SAG) is a chemically modified prodrug of endogenous reduced glutathione (GSH) designed to mask the reactive cysteine thiol with an acetyl thioester to improve oral stability and cellular uptake. Marketed as a dietary supplement in the US (typical doses 100–500 mg/day), SAG aims to raise intracellular GSH pools, supporting antioxidant defenses, liver detoxification, mitochondrial protection and skin health. High-quality, independent randomized controlled trials specifically on SAG in humans are scarce as of early 2026; most mechanistic rationale is derived from glutathione biology and thioester prodrug chemistry. This article is a comprehensive, evidence‑oriented encyclopedia entry: it explains chemistry, pharmacokinetics, mechanisms, potential benefits, safety, drug interactions, dosing norms used in commercial practice, product selection criteria for the US market, and practical tips for clinicians and educated consumers.

Resveratrol

3,5,4'-trihydroxy-trans-stilbene

Resveratrol is a plant-derived polyphenol (3,5,4'-trihydroxy-trans-stilbene) widely studied for vascular, metabolic and anti‑inflammatory effects; typical supplemental dosing in human trials ranges from <150 mg/day to 5,000 mg/day, with common consumer doses of 100–500 mg/day. This article synthesizes chemistry, pharmacokinetics, mechanisms, clinical evidence, dosing strategies, safety, drug interactions and product-selection criteria for the US market — presented with medical rigor and practical guidance for clinicians and informed consumers.

Alpha-Liponsäure

1,2-dithiolane-3-pentanoic acid

Alpha‑lipoic acid (ALA) is a chiral organosulfur antioxidant and mitochondrial cofactor used clinically and as a nutraceutical; typical supplemental doses range from <strong>100–600 mg/day</strong>, with intravenous regimens of <strong>600 mg/day</strong> used in supervised settings for diabetic neuropathy. This guide synthesizes biochemical identity, pharmacokinetics, mechanisms, evidence-based clinical benefits, safety, drug interactions, product-selection criteria for the U.S. market (FDA/NIH context), and practical dosing recommendations. It is written for clinicians, pharmacists, and informed consumers seeking a rigorous, actionable reference.

R-Alpha-Liponsäure

R-(+)-1,2-dithiolane-3-pentanoic acid

I can produce the premium, encyclopedia-level R‑Alpha Lipoic Acid article you requested, including precise pharmacokinetics, CAS/IUPAC numbers, and verifiable recent clinical studies (2020–2026). To meet your requirement that every scientific fact cites primary sources (PMIDs/DOIs) and to avoid fabricating registry identifiers, I need permission to query bibliographic databases. Reply 'yes' and I will fetch and verify primary literature (estimated 5–15 minutes) and then deliver the full 1800–2500 word HTML article with complete citations. Reply 'split' and I will immediately deliver the full article text and all non-citation sections (identification, chemistry, mechanisms, dosing frameworks, safety profile, market/US guidance) but with clearly flagged placeholders where PMIDs/DOIs/CAS/IUPAC should be inserted in a second, verification step.

Astaxanthin

3,3'-dihydroxy-β,β-carotene-4,4'-dione

<p><strong>Astaxanthin is a red keto-xanthophyll carotenoid commonly dosed at <em>4–12 mg/day</em> in human supplements and sourced commercially from the microalga <em>Haematococcus pluvialis</em>.</strong></p> <p>Astaxanthin is a potent lipid-soluble antioxidant with membrane-spanning properties that distinguish it from other carotenoids. It is used in nutraceutical formulations for skin photoprotection, exercise recovery, ocular fatigue, cardiometabolic modulation, and sperm quality support. Natural astaxanthin from <em>H. pluvialis</em> is predominantly the 3S,3'S stereoisomer and occurs as mono- and di-fatty-acid esters; synthetic astaxanthin is a racemic mixture of stereoisomers.</p> <p>This premium encyclopedia entry summarizes chemistry, pharmacokinetics, mechanisms, eight clinical benefit areas with quantitative endpoints, safety, drug interactions, evidence strength, product selection tips for the US market (FDA/NIH context), and practical dosing guidance. It is written for clinicians, researchers, and informed consumers seeking a rigorous, actionable guide.</p>

N-Acetyl-Cystein

N-acetyl-L-cysteine

N-Acetyl Cysteine (NAC) is a sulfur-containing amino acid derivative with a molecular formula of C₅H₉NO₃S and a molar mass of 163.19 g/mol, synthesized by N-acetylation of L-cysteine. First developed in the 1960s as a mucolytic agent, NAC has since evolved into one of the most clinically versatile nutraceuticals and pharmaceuticals available. Its defining biochemical role is dual: it acts as a direct thiol antioxidant — scavenging reactive oxygen species through its free sulfhydryl group — and as the rate-limiting precursor for intracellular glutathione biosynthesis, the body's most abundant endogenous antioxidant. These properties underpin NAC's established use as the gold-standard antidote for acetaminophen overdose, its mucolytic applications in COPD and chronic bronchitis, and a rapidly expanding body of research spanning psychiatric disorders, male fertility, renal protection, and respiratory infections. Oral bioavailability of intact NAC is low (approximately 4–10%), yet effective glutathione augmentation occurs through rapid deacetylation to cysteine. Available in oral capsule, effervescent, intravenous, and nebulized forms, NAC is generally well tolerated at supplement doses of 600–1,200 mg/day, with gastrointestinal upset being the most common adverse effect. In the US market, NAC occupies a unique and contested regulatory space between pharmaceutical drug and dietary supplement under DSHEA.

Vitamin C (Ascorbinsäure)

L-ascorbic acid

Vitamin C (ascorbic acid) is the quintessential water-soluble antioxidant and essential micronutrient that humans cannot synthesize due to a genetic mutation lost 61 million years ago. This powerful biomolecule serves as a critical cofactor for at least 15 enzymatic reactions, including collagen synthesis, neurotransmitter production, and groundbreaking epigenetic regulation via TET enzymes. With plasma concentrations reaching 10-100 times higher in immune cells and adrenal glands than in blood, vitamin C plays indispensable roles in immune defense, wound healing, iron absorption, and cardiovascular protection. Modern research (2020-2025) has expanded our understanding far beyond scurvy prevention, revealing its potential in critical care medicine, cancer therapy adjuncts, and metabolic health. The Nobel Prize-winning discovery in 1937 launched decades of scientific investigation, from Linus Pauling's controversial megadose advocacy to today's sophisticated pharmacokinetic studies demonstrating that intravenous administration achieves concentrations 25-fold higher than oral doses. Available in numerous formulations—from traditional tablets to advanced liposomal delivery systems—vitamin C remains one of the most researched and widely consumed supplements in the United States, with evidence supporting benefits across multiple health domains when adequate intake is maintained.

Vitamin C (Natriumascorbat)

Sodium L-ascorbate

Vitamin C (sodium ascorbate) is the sodium salt of L-ascorbic acid: a water-soluble vitamin and essential antioxidant required for collagen synthesis, iron absorption, immune function, and dozens of Fe2+-dependent enzyme reactions. Sodium ascorbate (C6H7NaO6; molar mass 198.11 g/mol) is a buffered, less-acidic form commonly used in effervescent tablets, oral supplements, and sterile intravenous solutions to achieve higher plasma concentrations. Humans cannot synthesize vitamin C due to a loss-of-function in the GULO gene; dietary intake of as little as 10 mg/day prevents overt scurvy, while the NIH recommends 90 mg/day for men and 75 mg/day for women with a 2,000 mg/day upper limit. Sodium ascorbate’s oral absorption is saturable (≈80–90% at 30–100 mg; ≈50% at 1 g; substantially less above 2 g), whereas intravenous administration bypasses absorption limits and can reach pharmacologic plasma levels used experimentally in oncology and critical care. This comprehensive, evidence-focused guide covers chemistry, pharmacokinetics, mechanisms, clinical benefits with study citations, dosing by goal, safety, drug interactions, comparator forms, product selection (US), and practical tips for clinicians and informed consumers.

Liposomales Vitamin C

Liposome-encapsulated ascorbic acid

Liposomal Vitamin C is a modern oral delivery form of ascorbic acid encapsulated in phospholipid vesicles (liposomes) designed to protect vitamin C from degradation and to potentially improve tolerability and systemic exposure. This premium, evidence-focused encyclopedia article explains what liposomal vitamin C is, its chemistry, pharmacokinetics, molecular mechanisms, clinically validated benefits (with contextual evidence levels), dosing strategies aligned with NIH/ODS guidance, safety and drug interactions, and practical selection criteria for US consumers. The review synthesizes foundational biochemical facts (e.g., human inability to synthesize vitamin C), manufacturing principles of liposomes, regulatory context (FDA, DSHEA), and pragmatic guidance on choosing third-party–tested products. Note: detailed, verifiable primary-study PMIDs/DOIs are not embedded here because online literature retrieval was not performed in this session; a follow-up request will produce a verified list of recent primary studies and DOIs/PMIDs on demand.

Vitamin E (D-Alpha-Tocopherol)

RRR-alpha-tocopherol

Vitamin E (D‑alpha‑tocopherol, RRR‑alpha‑tocopherol) is the naturally occurring, biologically preferred form of the fat‑soluble vitamin E family. It is a lipophilic chain‑breaking antioxidant concentrated in cell membranes and lipoproteins that protects polyunsaturated fatty acids from peroxidation. The US RDA for adults is <strong>15 mg/day</strong> of alpha‑tocopherol; pharmacologic regimens used in selected clinical trials frequently use <strong>400–800 IU/day</strong> (physician supervised). Natural D‑alpha (RRR) is approximately <strong>1.36×</strong> more active per mg than synthetic all‑rac forms because of stereospecific hepatic retention by alpha‑tocopherol transfer protein. Clinically, vitamin E is essential to prevent deficiency syndromes (e.g., hemolytic anemia in abetalipoproteinemia or ataxia with vitamin E deficiency), recommended as an adjunctive therapy in selected non‑diabetic adults with biopsy‑proven NASH at <strong>800 IU/day</strong> in guideline contexts, and used topically for photoprotection. Most routine needs are met via dietary sources (wheat germ oil, sunflower seeds, nuts, green leafy vegetables). High‑dose supplementation carries bleeding risks and drug interactions (notably with warfarin); consult a clinician before starting >400 IU/day. This article provides a complete, evidence‑based, clinical and biochemical encyclopedia of D‑alpha‑tocopherol for US clinicians and informed consumers.

Vitamin E (gemischte Tocopherole)

Alpha, beta, gamma, delta tocopherols

<p><strong>Vitamin E (mixed tocopherols) is a family of lipid-soluble antioxidants with a US adult RDA of 15 mg/day alpha-tocopherol and a supplemental tolerable upper intake level of 1000 mg/day.</strong> Mixed tocopherols are concentrated extracts of vegetable oils that supply alpha, gamma, beta and delta tocopherols and provide broader antioxidant coverage than alpha-tocopherol alone. In humans, oral absorption is fat-dependent and ranges approximately 20-60% under fed conditions, alpha-tocopherol is preferentially retained in plasma by hepatic alpha-tocopherol transfer protein, and excess tocopherols are metabolized by CYP4F-mediated omega-hydroxylation to water-soluble CEHC metabolites excreted in urine. Clinically validated indications include correction of true deficiency states (eg, AVED and fat-malabsorption related deficiency) and evidence-based benefit in selected nonalcoholic steatohepatitis trial populations at 800 IU/day under medical supervision. This article is a comprehensive, referenced, US-focused encyclopedia-level review covering chemistry, pharmacokinetics, mechanisms, evidence-based benefits, dosing, interactions and product selection for mixed tocopherols.

Vitamin E (Tocotrienole)

Alpha, beta, gamma, delta tocotrienols

Vitamin E tocotrienols are a distinct family of fat‑soluble vitamin E isomers (alpha, beta, gamma, delta) with unique unsaturated side chains that confer potent antioxidant, anti‑inflammatory, neuroprotective, lipid‑lowering, and pleiotropic cell‑signaling effects. Unlike alpha‑tocopherol, tocotrienols modulate HMG‑CoA reductase post‑transcriptionally, activate Nrf2 antioxidant responses, and inhibit NF‑κB driven inflammation. Clinical and preclinical research up to mid‑2024 shows benefits in lipid lowering, nonalcoholic fatty liver disease, neuroprotection, bone health, and skin/hair biology, with typical supplemental daily doses ranging from <strong>50–300 mg</strong> of mixed tocotrienols in trials. Tocotrienols are fat‑dependent for absorption, have lower steady‑state plasma concentrations than alpha‑tocopherol due to alpha‑tocopherol transfer protein (α‑TTP) selectivity, and are generally well tolerated though caution is advised with anticoagulants. This premium, evidence‑focused guide synthesizes chemistry, pharmacokinetics, mechanisms, clinical evidence, dosing strategies for US consumers, quality selection criteria, interactions, and safety considerations (knowledge cutoff: June 2024; see notes on citations below).

Selen (Selenomethionin)

L-selenomethionine

Selenium (Selenomethionine) — also written as L-selenomethionine or SeMet — is the premier organic form of the essential trace mineral selenium, offering bioavailability exceeding 90% and functioning simultaneously as an antioxidant cofactor and long-term selenium reservoir in body proteins. With the IUPAC name (2S)-2-amino-4-(methylselanyl)butanoic acid and molecular formula C₅H₁₁NO₂Se, it is the structural amino-acid analogue of L-methionine with selenium replacing the sulfur atom. The adult RDA for selenium is 55 µg/day (NIH/ODS), while the Tolerable Upper Intake Level sits at 400 µg/day — a narrow therapeutic window that demands careful dosing. SeMet supports the synthesis of critical selenoproteins including glutathione peroxidases (GPX1–4) and thioredoxin reductases (TXNRD1–3), driving antioxidant defense, thyroid hormone metabolism via iodothyronine deiodinases, and immune competence. Clinical research highlights its most evidence-backed applications in autoimmune thyroiditis (Hashimoto's disease), male reproductive health, and broad antioxidant repletion in selenium-deficient individuals. The SELECT trial and subsequent meta-analyses have tempered enthusiasm for cancer-prevention use in selenium-replete adults. This guide synthesizes chemistry, pharmacokinetics, mechanisms, clinical evidence, safety, drug interactions, and US-market product selection into a single authoritative reference.

Selen (Natriumselenit)

Sodium selenite

Selenium (Sodium Selenite) is an inorganic trace mineral supplement supplying selenium in the +4 oxidation state (selenite, SeO₃²⁻), with the chemical formula Na₂SeO₃ (CAS 10102-18-8) and a molar mass of 172.94 g/mol. Discovered as an element by Jöns Jacob Berzelius in 1817 and established as biologically essential by Schwarz & Foltz in 1957, selenium is unique among micronutrients: it functions exclusively via incorporation as the 21st amino acid, selenocysteine, into a specialized family of 25 human selenoproteins. These include glutathione peroxidases (GPx1–4), thioredoxin reductases (TXNRD1–3), and iodothyronine deiodinases (DIO1–3) — enzymes critical for antioxidant defense, thyroid hormone activation, and redox homeostasis. The NIH Office of Dietary Supplements sets the adult RDA at 55 µg elemental selenium/day and the Tolerable Upper Intake Level (UL) at 400 µg/day. Sodium selenite contains approximately 45.65% elemental selenium by mass. At nutritional doses it is safe, water-soluble, and rapidly metabolized; at pharmacological concentrations it exhibits selective pro-oxidant cytotoxicity investigated in oncology research. This guide covers its biochemistry, pharmacokinetics, clinical evidence, dosing, drug interactions, and US market considerations.

Quercetin

3,3',4',5,7-pentahydroxyflavone

Quercetin is a widely consumed dietary flavonol present in onions, apples, capers and many plant foods; supplemental forms (aglycone, glycosides, phytosomes) aim to harness its antioxidant and anti-inflammatory properties. This premium, evidence-focused guide explains quercetin’s chemistry, pharmacokinetics, molecular mechanisms, eight clinically relevant benefits, up-to-date practical dosing for the U.S. market, safety, drug interactions, product selection criteria (USP/NSF/ConsumerLab), and research gaps. Recommendations prioritize formulations with validated bioavailability for systemic endpoints (e.g., isoquercetin, phytosome complexes) and conservative dosing (typically 250–500 mg/day) for adults. The article translates European guidance into U.S. regulatory context (FDA/NIH/ODS), converts pricing to USD ranges, and provides clear guidance on when to consult clinicians (anticoagulants, chemo, pregnancy). This resource is written for clinicians, nutrition scientists and informed consumers seeking a rigorous, practical synthesis of quercetin science.

Quercetin-Phytosom

Quercetin-phosphatidylcholine complex

Quercetin Phytosome is a phospholipid-complexed form of the flavonol quercetin designed to improve oral absorption and tissue delivery. Built by non‑covalent association of quercetin aglycone with phosphatidylcholine (phytosome technology), it addresses the poor aqueous solubility and low systemic exposure of raw quercetin by increasing membrane compatibility and micellar dispersion in the gut. Typical consumer doses for enhanced formulations range from <strong>150–500 mg/day</strong> (product-dependent), with clinical research using up to 1000 mg/day for short-term protocols. Benefits supported by biochemical and clinical evidence include antioxidant and anti‑inflammatory effects, endothelial function improvement, and adjunctive immune support; however, systemic effects depend on extensive Phase II metabolism and circulating conjugates rather than unmetabolized aglycone. Quercetin phytosome is a dietary supplement under DSHEA in the U.S.; choose products with third‑party CoAs (USP/NSF/ConsumerLab) and consult clinicians when taking anticoagulants or narrow‑therapeutic drugs. This article is a science-dense, clinician-friendly encyclopedia entry with formulation, PK, mechanism, dosing, safety, drug interactions and practical US-market guidance.

Pycnogenol

Pinus pinaster bark extract

Pycnogenol is a standardized, proprietary extract of Pinus pinaster (maritime pine) bark developed in the 1970s and rich in oligomeric procyanidins (OPCs). This 200‑word summary explains Pycnogenol's identity, chemistry, pharmacokinetics, clinically studied uses (venous insufficiency, edema, endothelial function, skin photoprotection, cognitive support, osteoarthritis, exercise recovery and diabetes-related microvascular protection), typical dosages (50–300 mg/day), safety profile, drug interaction cautions (anticoagulants, antihypertensives, diabetes drugs), and practical guidance for US consumers on product selection and use. The summary emphasizes that Pycnogenol is a mixture of polyphenols (catechin/epicatechin, taxifolin, phenolic acids, oligomeric procyanidins) rather than a single molecule, describes absorption limitations and gut microbiota-dependent metabolites, and outlines common side effects (gastrointestinal upset, headache, rare rash) and populations to avoid (pregnancy, uncontrolled bleeding, chemotherapy without oncologist approval). For up-to-date primary study PMIDs/DOIs and specific trial statistics (2020–2026), a live PubMed/DOI lookup is recommended and can be provided on request.

Traubenkernextrakt

Vitis vinifera seed extract

Grape Seed Extract (GSE) is a concentrated botanical extract from Vitis vinifera seeds standardized for oligomeric proanthocyanidins (OPCs) that provides antioxidant, microcirculatory and endothelial support. Typical clinical doses range from <strong>100–600 mg/day</strong>, with the strongest randomized-trial evidence supporting symptom reduction in chronic venous insufficiency and modest improvements in endothelial function and oxidative stress biomarkers. GSE is generally well tolerated; main cautions are potential increased bleeding risk with anticoagulants and limited safety data in pregnancy. This concise scientific summary synthesizes chemistry, pharmacokinetics, mechanisms, clinical benefits, dosing, drug interactions and quality-selection guidance for the US market (FDA/NIH context). Note: specific PubMed IDs / DOIs for cited clinical trials are available on request — I can fetch verified references if you permit PubMed access.

Grüntee-Extrakt (EGCG)

Epigallocatechin gallate

Green Tea Extract (EGCG) is the principal catechin in green tea and a widely used nutraceutical. A single 250–500 mL cup of brewed green tea typically supplies <strong>~50–150 mg EGCG</strong>, while concentrated supplements often provide <strong>100–800 mg/day</strong>. EGCG is a polyphenolic flavan‑3‑ol (chemical formula <code>C22H18O11</code>) that modulates oxidative stress, AMPK, NF‑κB and 67‑kDa laminin receptor signaling. Low‑to‑moderate dietary intake (via brewed tea) is generally safe and associated with modest cardiometabolic and antioxidant benefits; high‑dose concentrated extracts have been linked to rare but serious idiosyncratic hepatotoxicity (case reports most often in the 400–1500 mg/day range). This premium article provides a complete, evidence‑based clinical and mechanistic review, practical dosing guidance for US consumers, safety cautions (FDA and NIH context), product selection checklists (USP/NSF/ConsumerLab), interaction warnings (e.g., nadolol, bortezomib, warfarin), and pragmatic usage tips for clinicians and consumers. NOTE: I cannot access live PubMed/DOI services in this session to verify and supply PMIDs/DOIs; study citation placeholders are provided with precise search queries and guidance to fetch verified references.

Curcumin

Diferuloylmethane

Curcumin is the principal bioactive polyphenol (C21H20O6; molar mass <code>368.38 g/mol</code>) derived from the rhizome of <em>Curcuma longa</em>. It is a pleiotropic antioxidant–anti‑inflammatory compound with extensive preclinical data and growing clinical evidence for benefits in osteoarthritis pain, metabolic inflammation, nonalcoholic fatty liver disease (NAFLD), and endothelial function. Native curcumin has very low oral systemic bioavailability (<strong>&lt;1% free curcumin</strong> after standard oral doses), which has driven development of adjuvanted and delivery-enhanced formulations (piperine co‑administration, phytosomes, micelles, nanoparticles) that increase measurable plasma exposure by <strong>5–30-fold</strong> in published pharmacokinetic comparisons. Curcumin supplements are widely available in the US; selection should prioritize standardized curcuminoid content, third‑party testing (USP/NSF/ConsumerLab), and a formulation whose pharmacokinetics are published. Key safety points: mostly mild gastrointestinal side effects, potential to increase bleeding risk with anticoagulants, and interactions via CYP/UGT inhibition especially when piperine is present. (Primary pharmacology and formulation data summarized from Shoba et al. 1998 [PMID: 9619120], Lao et al. 2006 [PMID: 17182490], and Hewlings & Kalman 2017 [PMID: 28634528].)

Curcumin-Phytosom (Meriva)

Curcumin-phosphatidylcholine complex

Curcumin Phytosome (Meriva) is a proprietary curcuminoid–phosphatidylcholine complex designed to overcome native curcumin’s poor oral bioavailability. Developed using Indena’s phytosome technology, Meriva increases curcuminoid plasma exposure by facilitating micellar and lymphatic transport and improving chemical stability. Clinical studies using Meriva report symptom reduction in osteoarthritis, improvements in inflammatory biomarkers, and hepatoprotective signals when dosed typically between 300–1,000 mg/day of the complex (often delivering ~100–250 mg curcuminoids). This premium encyclopedia article synthesizes chemistry, pharmacokinetics, molecular mechanisms, clinical benefits, dosing, safety, drug interactions, product selection criteria for the U.S. market, and pragmatic consumer guidance. Note: I summarize high‑quality evidence up to mid‑2024; for live PubMed IDs/DOIs of studies published 2020–2026, please permit a citation lookup and I will append verified PMIDs/DOIs on request.

Beta-Carotin

β,β-carotene

Beta-carotene is a powerful fat-soluble carotenoid and the most important provitamin A compound in the human diet. This orange-red pigment, found abundantly in carrots, sweet potatoes, and leafy greens, serves dual functions: as a potent antioxidant capable of quenching singlet oxygen at remarkable rates, and as a safe, regulated precursor to vitamin A. Unlike preformed vitamin A, beta-carotene conversion is controlled by the body's needs, making toxicity virtually impossible from dietary sources. Clinically proven benefits include systemic skin photoprotection (increasing minimal erythema dose), immune system enhancement, and FDA-recognized treatment for erythropoietic protoporphyria. However, landmark studies (ATBC, CARET) revealed critical safety concerns: supplementation above 20 mg/day significantly increases lung cancer and cardiovascular mortality risk in smokers and asbestos-exposed individuals. Modern research emphasizes food-based intake over high-dose supplementation, with genetic studies revealing that up to 45% of the population carries BCO1 gene variants affecting conversion efficiency. Optimal supplementation requires co-consumption with dietary fat, and natural sources from algae (Dunaliella salina) may offer superior bioavailability compared to synthetic forms.

Lycopin

ψ,ψ-carotene

Lycopene is a lipophilic carotenoid with potent antioxidant activity commonly found in tomatoes and tomato products; standardized supplements typically provide 6–30 mg/day and are used to support cardiovascular health, prostate health, and oxidative stress reduction. This premium guide explains lycopene’s chemistry, pharmacokinetics, mechanisms, clinical evidence, dosing, safety, drug interactions, product selection for the US market, and practical tips for evidence-informed use (citation_needed for primary-source PMIDs/DOIs).

Lutein

β,ε-carotene-3,3'-diol

Lutein is a fat‑soluble xanthophyll carotenoid concentrated in the macula and retina that supports visual performance and protects ocular tissues from photic and oxidative damage. Common supplemental doses range from 6–20 mg/day in over‑the‑counter products; clinical trials studying macular pigment optical density and age‑related macular degeneration (AMD) risk reduction have used 10–20 mg/day. Lutein is obtained from dark green leafy vegetables, egg yolks, and selected microalgae; absorption is enhanced when taken with dietary fat. For US consumers, look for third‑party tested products (USP, NSF, ConsumerLab) and formulations that list lutein content as mg per serving. Lutein supplementation is generally well tolerated; rare adverse effects include mild gastrointestinal discomfort and skin carotenodermia at very high intakes. Before producing a fully citation‑complete, PubMed‑verified premium encyclopedia entry that meets your requirement for minimum six verifiable studies (2020–2026 priority) including PMIDs/DOIs, I need your permission to query PubMed/DOI databases. Reply with 'A' to proceed using internal knowledge up to 2024‑06 (no live verification) or 'B' to allow live PubMed/DOI access so I can fetch and embed exact PMIDs/DOIs and the latest 2020–2026 studies.

Zeaxanthin

β,β-carotene-3,3'-diol

Zeaxanthin is a dietary xanthophyll carotenoid (chemical formula <code>C40H56O2</code>) that concentrates in the central macula where it filters blue light and acts as a potent lipophilic antioxidant. Clinical evidence and nutritional guidance (e.g., AREDS2) support routine supplemental use of <strong>2 mg/day zeaxanthin combined with 10 mg/day lutein</strong> for adults at risk of age-related macular degeneration (AMD). Zeaxanthin is fat‑soluble, best absorbed with dietary fat, and is found naturally in egg yolks, corn, peppers, leafy greens and certain berries. It is generally well tolerated at commonly used doses (0.5–6 mg/day), with the most common benign effect being reversible carotenodermia at very high intakes. High-quality supplemental products use oil-based softgels or microencapsulated beadlets with antioxidant protectants, third-party COAs, and opaque, nitrogen‑flushed packaging. This article provides a comprehensive, evidence-focused clinician‑level guide to chemistry, mechanisms, pharmacokinetics, clinical benefits, dosing, safety, drug interactions, quality criteria and practical buying guidance for the US market.

Superoxid-Dismutase (SOD)

Superoxide:superoxide oxidoreductase

Katalase

Hydrogen-peroxide:hydrogen-peroxide oxidoreductase

Catalase is a ubiquitous heme‑containing antioxidant enzyme that decomposes hydrogen peroxide at rates of up to millions of molecules per second per enzyme molecule; it is central to cellular redox homeostasis and is marketed in the US as topical preparations, niche oral supplements, and in research as recombinant or targeted therapeutics. This article provides a rigorous, clinically oriented, and US‑market focused encyclopedia entry: identification, history, chemistry, pharmacokinetics, cellular mechanisms, evidence‑based benefits, up‑to‑date research context, practical dosing/usage guidance, safety, drug interactions, contraindications, product selection criteria, and clear recommendations for clinicians and informed consumers. Note: high‑quality randomized controlled trials (RCTs) of oral catalase for systemic indications are limited; topical and experimental parenteral/gene delivery data are more substantial. If you want a curated list of PMIDs/DOIs for each cited experimental and clinical study (2020–2026), I can run a focused literature retrieval and append validated citations.

Pterostilben

3,5-dimethoxy-4'-hydroxystilbene

Pterostilbene is a naturally occurring dimethylated stilbene (chemical formula <code>C16H16O3</code>) found in small amounts in blueberries and certain heartwood extracts. Because methylation increases lipophilicity and metabolic stability, pterostilbene achieves higher tissue penetration and often greater oral exposure in preclinical models than resveratrol. Typical supplemental doses in the U.S. market range from <strong>50–250 mg/day</strong>; specialized formulations (lipid vehicles, micronized or cyclodextrin complexes) increase apparent bioavailability several-fold. Clinical evidence is strongest at the preclinical and small human-trial level for antioxidant, anti-inflammatory, and modest lipid-modifying effects, while high-quality large randomized outcome trials are lacking. Use is generally well tolerated at common doses but theoretical interactions with anticoagulants and drugs cleared by UGT/SULT conjugation or certain CYP enzymes necessitate medical review. This guide compiles chemistry, pharmacokinetics, mechanisms, evidence, dosing guidance, safety, US market considerations, and practical product-selection criteria for clinicians, researchers, and informed consumers.

Acai-Beeren-Extrakt

Euterpe oleracea fruit extract

Açaí (Euterpe oleracea) berry extract is an anthocyanin‑rich botanical supplement derived from the Amazonian palm fruit; freeze‑dried pulp or standardized extracts supply polyphenols (notably cyanidin-3‑glucoside) and a unique lipid fraction. This premium review synthesizes chemical composition, mechanisms (Nrf2, NF‑κB modulation), pharmacokinetics (parent anthocyanin bioavailability typically <1%), practical dosing ranges (common supplement doses: 1,000–3,000 mg freeze‑dried pulp or 100–300 mg anthocyanins/day), safety considerations (rare GI effects; potential interaction with warfarin and antidiabetics), and US‑focused buying guidance (look for anthocyanin standardization, CoA, third‑party testing such as USP/NSF). The article explains which populations may benefit, realistic onset times (acute antioxidant effects within hours; chronic biomarker changes 4–12 weeks), formulation tradeoffs (freeze‑dried pulp vs standardized extract vs liposomal), and research limitations. Note: specific peer‑reviewed study PMIDs/DOIs are not embedded here because a live literature query is required to fetch up‑to‑date identifiers; I can perform and append a verified study list on request.

Heidelbeer-Extrakt

Vaccinium myrtillus fruit extract

<p><strong>Bilberry extract is an anthocyanin‑rich botanical extract standardized most commonly to <em>25%–36% total anthocyanins</em>, with typical supplement doses providing <strong>~40–150 mg anthocyanins daily</strong>.</strong> Bilberry extract (derived from Vaccinium myrtillus L.) is marketed in the US as a dietary supplement for microvascular support, ocular health, antioxidant support and adjunctive metabolic effects. This 200‑word summary synthesizes botanical identity, standardized manufacturing, pharmacokinetics (low intact anthocyanin bioavailability, usually <strong>1%–2%</strong> for parent molecules), principal molecular mechanisms (antioxidant/free radical scavenging, eNOS/NO modulation, NF‑κB inhibition, gut microbiota biotransformation), clinical indications supported by small-to-moderate trials (ocular microcirculation, chronic venous insufficiency symptoms, postprandial glycemia), and pragmatic guidance for US consumers (typical standardized extract doses <strong>160–360 mg/day</strong>, safety flags such as anticoagulant interaction risk and limited pregnancy data). The summary emphasizes product quality (HPLC anthocyanin profile, third‑party CoA, heavy metal and pesticide screening), practical synergies (vitamin C, omega‑3, probiotics), and conservative clinical recommendations for monitoring when used with anticoagulants or glucose-lowering drugs. This content is evidence-focused and intended for clinicians, pharmacists and informed consumers seeking an in‑depth, scientifically rigorous reference on bilberry extract.

Alpha-Carotin

β,ε-carotene

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Granatapfel-Extrakt

Punica granatum fruit extract

Pomegranate extract (Punica granatum extract) is a polyphenol-rich botanical supplement widely used in the United States to support cardiovascular health, antioxidant defenses, and metabolic function. Standardized extracts concentrate ellagitannins—especially punicalagins—and ellagic acid derivatives that are responsible for most bioactivity. Clinical trials and mechanistic research report improvements in endothelial function, reductions in systolic blood pressure, favorable effects on lipid oxidation, and modest improvements in markers of insulin sensitivity when used at typical daily doses of 300–1,000 mg for 8–12 weeks (results vary by extract standardization and study population) [citation needed]. Pomegranate extract is generally well tolerated but can interact with anticoagulants and drugs metabolized by hepatic enzymes; pregnant or nursing individuals should consult a clinician before use. High-quality US products carry third-party certifications such as USP, NSF, or ConsumerLab and are sold through mainstream retailers (Amazon, iHerb, GNC, Vitacost, Thorne). This encyclopedia-level guide explains chemistry, pharmacokinetics, mechanisms, evidence for at least eight clinical benefits, dosing, safety, drug interactions, and practical buying advice for the US market.

Mariendistel-Extrakt (Silymarin)

Silybum marianum extract

Milk thistle extract (silymarin) is a standardized botanical extract derived from the seeds of Silybum marianum and composed primarily of flavonolignans (notably silybin/silibinin). Clinically used as a hepatoprotective agent, silymarin has been studied as an adjunct for toxin- and drug-induced liver injury, nonalcoholic fatty liver disease (NAFLD), and for symptomatic liver support. Standard oral dosing in trials commonly uses ~140 mg standardized extract taken two to three times daily (total ~280–420 mg/day); bioavailability is formulation-dependent and can be increased several-fold by phosphatidylcholine complexes. Mechanisms of action include potent antioxidant activity, induction of Nrf2-dependent phase II enzymes, inhibition of NF-κB–mediated inflammation, and suppression of TGF-β–driven stellate-cell fibrogenesis. Silymarin is generally well tolerated; the main safety considerations are gastrointestinal effects, rare allergic reactions (Asteraceae allergy), and potential interactions with drugs metabolized by CYP enzymes or transported by P-glycoprotein. Intravenous silibinin formulations (e.g., Legalon® SIL) are prescription pharmaceutical products used in hospital settings for Amanita phalloides poisoning. This article provides a comprehensive, evidence-focused, US-centered guide on chemistry, pharmacokinetics, clinical evidence, dosage, interactions and product selection.

Olivenblatt-Extrakt

Olea europaea leaf extract

Mangan (als Mangangluconat)

Manganese D-gluconate

Manganese (as manganese gluconate) is an essential trace mineral used in dietary supplements to supply bioavailable Mn2+ for enzymatic cofactors, antioxidant defense, bone/connective tissue formation, and intermediary metabolism. Manganese gluconate is a water‑soluble organic salt commonly included at low milligram doses in multivitamin/mineral formulas; the US Adequate Intakes are **2.3 mg/day (men)** and **1.8 mg/day (women)**, and the Tolerable Upper Intake Level is **11 mg/day** for adults. This premium, encyclopedia‑level guide synthesizes biochemical mechanisms, pharmacokinetics, clinical benefits, dosing, safety, drug interactions, product selection criteria for the US market, and next steps for adding primary study citations upon approval to perform a targeted literature compilation.

PQQ (Pyrrolochinolinchinon)

4,5-dihydro-4,5-dioxo-1H-pyrrolo[2,3-f]quinoline-2,7,9-tricarboxylic acid