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Immune System
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In one pass The immune system's goal is not to run at full power all the time.
Educational content, not medical advice — consult a clinician.
balance quartet The lay phrase boost your immune system has no matching concept in medicine.
Rhinovirus arrives Most rhinoviruses lock onto ICAM-1 receptors on the lining of the nose and nasopharynx, get in and replicate there, so a cold starts in the nose and throat.
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Chapter 1
Not stronger, smarter
The immune system's goal is not to run at full power all the time. It is to recognize accurately, respond in proportion, and brake once the job is done.
It works in two layers. Innate immunity can act within minutes; it does not pick its targets and keeps no memory. Adaptive immunity takes one to two weeks to train dedicated cells and antibodies, but it remembers the opponent. Too weak, and infections get through; too strong, or unable to brake, and the result is chronic inflammation, allergy or autoimmune disease. So boosting immunity asks the wrong question. The right one is whether the system is accurate and whether it can stop.
It works in two layers. Innate immunity can act within minutes; it does not pick its targets and keeps no memory. Adaptive immunity takes one to two weeks to train dedicated cells and antibodies, but it remembers the opponent. Too weak, and infections get through; too strong, or unable to brake, and the result is chronic inflammation, allergy or autoimmune disease. So boosting immunity asks the wrong question. The right one is whether the system is accurate and whether it can stop.
Mechanism · What each layer of immunity does
Immunity has two arms that work on very different timelines.Innate immunity responds within minutes, by pattern recognition. Sentries on cells — Toll-like receptors (TLRs) and NOD-like receptors (NLRs) — open fire as soon as they see molecular shapes that do not belong to a person: the lipopolysaccharide on a bacterial wall, the β-glucan in a fungal cell wall, viral RNA. The main players are macrophages, neutrophils, natural killer (NK) cells, the complement system, and antimicrobial peptides such as LL-37 that kill microbes directly on mucosal surfaces. It does not pick its targets, does not learn and keeps no memory.
Adaptive immunity takes 7–14 days to really arrive. T cells and B cells each carry a receptor of a different shape (the T-cell receptor, TCR, and the B-cell receptor, BCR), and each receptor recognizes one specific antigen: selective, learning, able to keep a memory. This is the layer vaccines train.
So a fever on day 1 of a cold is innate immunity sounding the alarm; antibodies around day 7 are adaptive immunity arriving. Nutrition affects both layers, but by different routes. Lymphocytes have to divide fast and need the raw materials for making DNA, so folate and vitamin B12 matter especially for adaptive immunity.
Mechanism · What happens during one cold
Immunity has a fast layer that never learns, and a slower layer that remembers. Put both on one timeline and follow an ordinary cold from start to finish — every miserable symptom maps onto one of the steps.Step 1 · The virus squeezes past the barrier. The nose and throat are coated in mucus, and the epithelial cells are sewn tightly together. To get to work, a virus has to dodge the mucus wash, dock on a receptor on an epithelial cell, then slip inside and borrow the cell's workshop to copy itself. When the barrier is in poor shape (dry mucosa, too little sleep), this step may be easier to break through. A lot of what people call immunity is lost first at the barrier, not at some mysterious master switch.
Step 2 · A sentry sees that this is not ours. Inside the infected cell sits a stretch of viral RNA that should not be there. The pattern-recognition receptors (TLRs, NLRs) standing inside and outside the cell do not know which virus this is. They know only one feature: a molecule shaped like this does not belong to a person. Recognition rings the alarm at once. This step needs no learning and no earlier encounter, so it can start within minutes.
Step 3 · The alarm is interferon. The infected cell releases a class of signal molecules called interferons into its neighborhood. Interferon does not kill virus. It warns the neighbors: nearby cells that are not yet infected switch their protein-making workshops into a guarded state, so that even if virus gets in, it cannot copy itself — like locking every house on the block in advance. The same alarm also reaches the temperature-control center in the brain, so you start to run a fever, shiver and ache. Those miserable feelings are not caused by the virus itself. They are the side effect of your own alarm system running wide open. At the same time, neutrophils and macrophages arrive to swallow what they can, and wave after wave of them die on the spot. When mucus turns from watery to thick and yellow-green, what you are seeing is large numbers of dead neutrophils.
Step 4 · Someone carries a sample to the rear. Another cell on the scene is doing a completely different job. A dendritic cell does not rush to kill. It holds fragments of the virus (antigen) on its own surface, leaves the scene, and travels along the lymph vessels into the nearest lymph node. This step is the hinge of the whole chain. Innate immunity buys time on site, but the cells that can remember this virus are not on site; they are waiting in the lymph node to see the sample.
Step 5 · In the lymph node: pick the right cells, then multiply them. The lymph node is packed with T cells and B cells, each with a differently shaped receptor that was set at random before it left the factory. The dendritic cell presents the antigen to one after another until it meets the small handful whose shape matches. Those few get a you're the one signal and start dividing hard: one becomes two, two become four, and within a few days a handful becomes a crowd. This is called clonal expansion. It is also where nutrition meets immunity: when immunity really has to work, its basic job is making cells, so folate, vitamin B12, iron and protein can become the bottleneck right here. The swollen, tender lymph node in your neck is that workshop expanding its army.
Step 6 · Antibodies take the field, and the front line changes hands. The expanded B cells start producing antibody in bulk. Antibody travels through blood and mucus across the body and seals the virus's surface, so it can no longer dock on a cell; meanwhile killer T cells clear away the cells that are already occupied, virus and all. This step is much slower than the ones before, so a cold is often at its worst early, and truly cleared later.
Step 7 · Brake, then keep a record. Once the virus is cleared, the system has to put the fire out. Neutrophils were short-lived anyway; regulatory T cells (Tregs) calm the troops that are still excited; inflammatory signals ebb, and tissue starts to repair. What happens when the brake fails is the subject of the later chapters on self-tolerance and chronic inflammation. Most of the expanded crowd stands down, but a small group of memory cells stays behind. Their receptors already match, and there are far more of them than the handful you started with.
String the seven steps together and three things follow that you can now work out for yourself:
Why a cold always takes a while to clear. It is not that the body reacts slowly — steps 2 and 3 happen within minutes. What is slow is picking the cells and building the army: turning a handful of cells into a force takes time in itself. In the first days of misery, innate immunity is buying time on site while the rear trains the troops.Why meeting the same virus a second time often does not make you ill. Memory cells do not have to be picked from scratch. They go straight to expansion on first contact, so the rear finally keeps pace with how fast the virus copies itself. The fight is over before the virus is numerous enough to need a whole-body alarm. You do not run a fever, not because your resistance is stronger this time, but because that stretch was skipped.Which layer a vaccine trains. A vaccine hands the immune system the sample from step 4 directly: it shows the system the virus's signature molecules without the damage a real virus causes. Many vaccines contain an adjuvant, which deliberately rings a small innate alarm so that the sample gets carried into the lymph nodes. Steps 5 and 7 then run as usual, and you already have memory cells before you ever meet the real virus. So a vaccine works on the adaptive layer. What it trains is recognizing accurately and quickly, not more firepower.
Turn it around, and marketing lines like boost your immunity have nowhere to land on this chain. Every step depends either on whether the barrier is intact, or on whether cells can be made on time and the signal braked on time. Nowhere on the chain is there a point that eating one particular thing turns up.
Chapter 2
Barrier first
Skin, the airways and the gut lining keep most threats out before anything else happens. Vitamin A lets epithelial cells mature normally into a complete layer; vitamin C helps make collagen, which keeps tissue strong; protein supplies the raw material for repair.
A lot of what people call immunity shows up first as the quality of these barriers. Cracked skin, mouth ulcers and a leakier gut are all a barrier letting water in.
A lot of what people call immunity shows up first as the quality of these barriers. Cracked skin, mouth ulcers and a leakier gut are all a barrier letting water in.
Mechanism · The four layers of the gut barrier
A large share of the body's immune cells are stationed in the gut lining, concentrated in the gut-associated lymphoid tissue (GALT).The gut barrier has four layers:
Mucus layer: goblet cells secrete mucin, which keeps bacteria from touching the epithelium directly.A single layer of epithelium: gut cells are sewn together by tight junctions (built from proteins such as occludin and claudin).Secretory IgA: made by plasma cells that develop from B cells, it holds gut bacteria in the mucus and away from the epithelium.GALT patrol: in Peyer's patches — lymphoid clusters in the gut wall — M cells actively sample what is in the gut and hand it to the immune cells beneath.
How tight the junctions are is regulated by zinc, glutamine, vitamin A and vitamin D. Laboratory and clinical studies suggest that long-term high blood glucose, alcohol, non-steroidal anti-inflammatory drugs (), stress and severe zinc deficiency all loosen them. That is the molecular basis behind the idea of a leaky gut. As a disease, leaky gut remains contested in mainstream medicine, but the fact that barrier permeability can change is well established.
Chapter 3
Cells must divide
Once immune cells are activated, they have to multiply fast while making antibodies and signal molecules. Folate, vitamin B12, iron, zinc and protein all take part in these most basic processes: making DNA, making protein, dividing.
So when nutrition falls short, it is not that some magic immunity switch has broken. Basic cell construction simply cannot keep up. Getting enough fills the gap; taking more when you are not short does not turn the system up.
So when nutrition falls short, it is not that some magic immunity switch has broken. Basic cell construction simply cannot keep up. Getting enough fills the gap; taking more when you are not short does not turn the system up.
Mechanism · The kinds of white blood cell
The white-cell differential on a blood test lists five kinds in the blood: neutrophils, lymphocytes, monocytes, eosinophils and basophils. Two more kinds of immune cell live mainly in tissues and do not show up in a blood draw: macrophages and dendritic cells.On the innate side:
Neutrophils: 50–70% of the white cells in blood. They are the first wave on the scene, swallowing bacteria, and they die within hours.Monocytes and macrophages: monocytes patrol the blood and can turn into macrophages once they enter tissue. Macrophages stay in tissues for a long time and are long-lived; Kupffer cells in the liver and microglia in the brain both belong to this family.Eosinophils and basophils: they deal with parasites and also take part in allergic reactions.Natural killer (NK) cells: counted among the lymphocytes, but they need no prior learning and no MHC recognition of an antigen; they kill virus-infected cells and some tumor cells directly.
On the adaptive side:
T cells: CD4 helper T cells (including the Th1, Th2 and Th17 subsets and regulatory T cells, Tregs) give the orders; CD8 killer T cells clear infected cells.B cells: once they mature into plasma cells, they secrete antibodies (IgM, IgG, IgA, IgE).
Dendritic cells sample tissue and carry antigen to the lymph nodes, bridging the two sides.
On a routine blood test, high neutrophils with low lymphocytes are common in acute bacterial infection; high lymphocytes look more like a viral infection. This points only in a direction and cannot be used to diagnose yourself, but it is one of the few signals on routine bloodwork where you can see the immune state directly.
Chapter 4
Telling self from invader
Every day the immune system makes its hardest call: is this molecule in front of me part of me, or an invader?
It can get the call wrong in three directions:
Treating foreign as self: the pathogen escapes, so an infection drags on or a tumor slips past immune surveillance.Treating self as foreign: the body's own tissue is attacked — that is autoimmune disease.Treating harmless as a threat: an overreaction to harmless things such as pollen or food — that is allergy.
What immunity needs is not more strength but more accuracy.
It can get the call wrong in three directions:
Treating foreign as self: the pathogen escapes, so an infection drags on or a tumor slips past immune surveillance.Treating self as foreign: the body's own tissue is attacked — that is autoimmune disease.Treating harmless as a threat: an overreaction to harmless things such as pollen or food — that is allergy.
What immunity needs is not more strength but more accuracy.
Mechanism · How the thymus screens T cells
T cells are trained in the thymus. The shape of each new T cell's receptor is assembled at random, so it has to pass two tests first:Test one: does it recognize the body's own MHC? MHC molecules are the display stands cells use to present antigen. A T cell that cannot recognize its own display stands at all is of no use and dies; only those that recognize them with moderate strength are kept. This is positive selection.Test two: is it too eager to attack the self? A gene in the thymus called AIRE makes thymic epithelial cells unusually express protein fragments from tissues all over the body (insulin, thyroglobulin, myelin basic protein, and more). T cells that react too strongly to these self-antigens are dangerous and are also eliminated. This is negative selection.
Between the two tests, about 95% of new T cells never leave the thymus.
A defect in the AIRE gene causes a rare inherited disease called APECED (autoimmune polyendocrinopathy–candidiasis–ectodermal dystrophy). Its classic triad is chronic mucocutaneous candidiasis (a persistent yeast infection of skin and mucosa), hypoparathyroidism and adrenal insufficiency (Addison's disease). One broken gene and self-tolerance fails across many organs, which shows that AIRE plays a causal role in building tolerance.
Peripheral tolerance: self-reactive T cells that slip through the thymus are held down throughout the body by regulatory T cells (Tregs). The master control gene of Tregs is FoxP3; mutations in FoxP3 cause IPEX syndrome, in which many autoimmune diseases appear in infancy and are often fatal.
Mechanism · Where autoimmunity and allergy come from
Autoimmune disease: tolerance has leaked, and antibodies or T cells attack the body's own tissue. Taken together these diseases are not rare. Common examples:Hashimoto's thyroiditis: attacks thyroid peroxidase ()Type 1 diabetes: attacks the insulin-making β cells of the pancreasRheumatoid arthritis: attacks the lining of the joints (synovium)Multiple sclerosis (MS): attacks the myelin sheath of nervesSystemic lupus erythematosus (SLE): attacks DNA and proteins in the cell nucleus, and affects many organs
In most autoimmune diseases women are affected clearly more often than men, by a margin that varies from disease to disease. Immune-related genes on the X chromosome and estrogen's effects on immunity are part of the explanation.
Allergy: treating something harmless as a threat. Classic immediate allergy is driven by IgE antibodies and leans toward a Th2-type response. It overreacts to molecules such as pollen, foods and dust mites, and shows up as rhinitis or asthma, and at its most severe as anaphylaxis. Some delayed allergic reactions do not involve IgE at all; they are driven by T cells, work differently, and should not be lumped together with IgE allergy.
The hygiene hypothesis: the modern rise in both allergy and autoimmune disease is thought to be linked to less contact with microbes in childhood (proposed by Strachan in 1989). It was later revised into the old friends hypothesis: what is missing is not bacteria as such, but the training the immune system used to get from the commensal microbes and parasites that evolved alongside humans. This is an explanatory framework, not a cause proven by trials.
On the nutrition side: vitamin D deficiency is associated with several autoimmune diseases (MS, type 1 diabetes, SLE). Laboratory studies suggest that active vitamin D [1,25(OH)₂D] increases Tregs and dampens Th17 cells — a plausible mechanism, not a settled one. Randomized-trial evidence for supplementing vitamin D to prevent autoimmune disease remains limited.
Where vitamin D does show an effect in trials is something else: acute respiratory infections. Martineau 2017 pooled individual-participant data from 25 double-blind randomized trials. Daily or weekly vitamin D reduced acute respiratory infections; the benefit was largest in people whose blood started below 25 nmol/L ( 0.30), while for those at 25 nmol/L or above the odds ratio was 0.75. One or more large bolus doses showed no benefit.
Chapter 5
More antioxidants isn't better
Immune responses produce oxidative stress, and they also need oxidative signals to kill pathogens: the main weapon neutrophils use to kill bacteria is an oxidative burst, a concentrated release of reactive oxygen species.
Selenium, zinc, copper, vitamin C and vitamin E all take part in the body's antioxidant network, but a high dose of any single one does not mean better immunity. By mechanism, suppressing oxidation too hard could blunt this killing power as well; that has not been shown directly in people.
Selenium, zinc, copper, vitamin C and vitamin E all take part in the body's antioxidant network, but a high dose of any single one does not mean better immunity. By mechanism, suppressing oxidation too hard could blunt this killing power as well; that has not been shown directly in people.
Evidence · Do zinc lozenges shorten colds?
Zinc shortening a cold is backed by a signal from randomized trials, but the certainty of the evidence is low — and many people use it the wrong way.What the trials used were zinc lozenges (zinc acetate or zinc gluconate), dissolved slowly in the mouth rather than swallowed: 75–100 mg of elemental zinc a day, taken in portions, starting within 24 hours of the first symptoms. Hemilä 2016, an individual-participant-data , pooled three randomized trials of zinc acetate lozenges (199 people in all) that used 80–92 mg/day; colds were about 2.7 days shorter on average. The current Cochrane review is Nault 2024, not the retracted Singh & Das version. Its conclusion: treating a cold with zinc may shorten it by about 2.4 days, but the certainty of the evidence is low and the studies differ enormously (I² = 97%); taking zinc every day to prevent colds makes little or no difference.
The mechanism usually proposed is that free zinc ions released from the lozenge in the nose and throat may stop rhinoviruses from binding ICAM-1, the receptor they attach to. That is still a hypothesis, so the following ways it may work less well are also reasoned from mechanism; no trial has compared them directly:
Swallowing zinc tablets: the zinc does not stay in the nose and throat.Lozenges made with citric or tartaric acid: these ingredients grab zinc ions, so less free zinc is released.Starting more than 24 hours after symptoms begin.
So taking zinc tablets every day to ward off colds has no support; sucking zinc lozenges from the first day of a cold has a trial signal behind it, with low certainty. On safety: high-dose zinc for more than 7 days in a row lowers copper absorption and can cause nausea and a metallic taste; Nault 2024 also found more non-serious side effects, such as nausea, in people treated with zinc.
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Chapter 6
Chronic low-grade inflammation
Acute inflammation repairs; chronic inflammation wears the body down. In middle and later life, a low-grade, persistent state of inflammation is common: interleukin-6 (), tumor necrosis factor () and C-reactive protein () in the blood all stay slightly raised. It is called inflammaging.
It is associated with type 2 diabetes, cardiovascular disease, Alzheimer's disease, osteoporosis and sarcopenia, and is thought to be one of the upstream factors these diseases share. But most of the evidence so far is association, and which link is cause and which is effect has not been fully sorted out.
It is associated with type 2 diabetes, cardiovascular disease, Alzheimer's disease, osteoporosis and sarcopenia, and is thought to be one of the upstream factors these diseases share. But most of the evidence so far is association, and which link is cause and which is effect has not been fully sorted out.
Mechanism · What pushes inflammation up and down
What pushes chronic inflammation up:Visceral fat: it is not just fat storage but an active endocrine organ that secretes and .Long-term high blood glucose: advanced glycation end-products (AGEs) build up, together with insulin resistance.Late nights and chronic stress: the cortisol rhythm is disrupted; by mechanism, the body's ability to hold down an inflammatory pathway () is weakened.A leaky gut barrier: small amounts of lipopolysaccharide (LPS) from bacterial walls enter the blood, a state called metabolic endotoxemia; its link to metabolic disease comes mainly from observational studies.
What brings chronic inflammation down:
Regular exercise: during exercise, muscle briefly releases IL-6 (here acting as a signal molecule secreted by muscle, a myokine); people who exercise regularly over the long term have lower markers of chronic inflammation.Sleeping 7–9 hours a night.Omega-3 fatty acids ( and ).Losing waist size: waist size reflects visceral fat and tracks this block more closely than body weight does.A Mediterranean-style, or whole-food-based, eating pattern.
Marker to watch: high-sensitivity C-reactive protein () below 1.0 mg/L counts as low risk, 1–3 as moderate, and above 3 as elevated (after ruling out an acute infection). These bands are the ones commonly used in cardiovascular risk assessment. It is one of the cheapest and most useful inflammation thermometers on a routine panel.
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References · 14
- National Institutes of Health, Office of Dietary Supplements. (2024). Vitamin D — Fact Sheet for Health Professionals. Fact sheet (updated June 27, 2025; Wayback snapshot 20 September 2026): 25(OH)D below 30 nmol/L (12 ng/mL) is associated with deficiency, 30 to below 50 nmol/L is generally considered inadequate, 50 nmol/L (20 ng/mL) or more is sufficient for most people, and above 125 nmol/L (50 ng/mL) can be associated with adverse effects; RDA 600 IU (15 mcg) to age 70 and 800 IU (20 mcg) above 70; adult UL 4,000 IU (100 mcg); older people and people with darker skin (more melanin) make less vitamin D from sunlight (fact sheet). ods.od.nih.gov/factsheets/VitaminD-HealthProfessional
- National Institutes of Health, Office of Dietary Supplements. (2022). Zinc — Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/Zinc-HealthProfessional
- National Institutes of Health, Office of Dietary Supplements. (2025). Vitamin A and Carotenoids — Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/VitaminA-HealthProfessional
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- Institute of Medicine. (2005). Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. National Academies Press. nap.nationalacademies.org/catalog/10490/dietary-reference-intakes-for-energy-carbohydrate-fiber-fat-fatty-acids-cholesterol-protein-and-amino-acids
- National Institutes of Health, Office of Dietary Supplements. (2022). Folate — Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/Folate-HealthProfessional
- National Institutes of Health, Office of Dietary Supplements. (2024). Vitamin B12 — Fact Sheet for Health Professionals. Fact sheet (updated July 2, 2025; Wayback snapshot 20 September 2026): multivitamin/mineral supplements typically contain 5 to 25 mcg B12, B-complex products 50 to 500 mcg, B12-only supplements typically 500 to 1,000 mcg; absorption is only about 2% at 500 mcg and 1.3% at 1,000 mcg; a 2018 Cochrane review of 3 RCTs (153 participants) compared very high oral doses (1,000-2,000 mcg) with intramuscular B12; high oral doses (e.g. 1,000 mcg/day) might be equally effective in Crohn's disease and appear as effective as hydroxocobalamin injections after Roux-en-Y bypass. These are product contents and trial doses; the sheet gives no recommended daily supplement range (fact sheet). ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional
- National Institutes of Health, Office of Dietary Supplements. (2024). Iron — Fact Sheet for Health Professionals. Fact sheet (updated September 4, 2025; Wayback snapshot 21 September 2026): RDAs 8 mg/day for men and for women 51+, 18 mg women 19-50, 27 mg pregnancy; UL 45 mg/day from age 14; bioavailability about 14%-18% from mixed diets with meat, seafood and vitamin C and 5%-12% from vegetarian diets; serum ferritin below 30 mcg/L suggests iron deficiency and below 10 mcg/L IDA, but inflammation can raise ferritin; supplemental iron of 45 mg/day or more may cause nausea and constipation; people with hereditary hemochromatosis are at risk of iron overload (fact sheet). Heme vs nonheme: heme iron (lean meat and seafood are the richest sources) has higher bioavailability than nonheme iron, and other dietary components affect it less; calcium might reduce the bioavailability of both forms; heme iron is about 10%-15% of total iron intake in western populations. The sheet gives no separate heme and nonheme absorption percentages (fact sheet, Wayback 2026 snapshot). ods.od.nih.gov/factsheets/Iron-HealthProfessional
- Martineau, A. R., et al. (2017). Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis. BMJ, 356, i6583. Individual-participant-data meta-analysis of 25 double-blind RCTs (11,321 participants aged 0-95; IPD for 10,933). Overall adjusted OR for acute respiratory infection 0.88 (0.81-0.96). Daily or weekly dosing without boluses OR 0.81 (0.72-0.91); one or more bolus doses OR 0.97 (0.86-1.10), no benefit. Among daily/weekly recipients: baseline 25(OH)D below 25 nmol/L OR 0.30 (0.17-0.53); 25 nmol/L or above OR 0.75 (0.60-0.95). Serious adverse events not increased (OR 0.98) (abstract, PMID 28202713). 10.1136/bmj.i6583
- National Institutes of Health, Office of Dietary Supplements. (2021). Selenium — Fact Sheet for Health Professionals. Table 2: Brazil nuts, 1 ounce (6-8 nuts), 544 mcg selenium (989% DV); the text says Brazil nuts contain 68-91 mcg per nut and could cause selenium toxicity if consumed regularly, and that values from other analyses vary widely. The version read carries 'Updated: April 15, 2024' (Wayback Machine snapshot of 31 December 2024), newer than the 2021 date above (fact sheet, read 2026-09-24). The September 4, 2025 update (Wayback snapshot 19 September 2026) adds: the body absorbs up to about 90% of selenium from selenomethionine, selenium-enriched yeast, selenite and selenate; selenium-only supplements typically contain 100 to 400 mcg; Keshan disease, an endemic cardiomyopathy first identified in 1935 in low-selenium parts of China, fell dramatically after selenium intervention trials in the 1970s-1990s; in 2017 the American Thyroid Association issued a weak recommendation against selenium supplements for TPOAb-positive pregnant women (fact sheet). ods.od.nih.gov/factsheets/Selenium-HealthProfessional
- National Institutes of Health, Office of Dietary Supplements. (2022). Copper — Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/Copper-HealthProfessional
- National Institutes of Health, Office of Dietary Supplements. (2021). Vitamin E — Fact Sheet for Health Professionals. ods.od.nih.gov/factsheets/VitaminE-HealthProfessional
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