Copper for Immune Function
Verdict: Published with Warning
Across 5 PubMed studies, the evidence for Copper in Immune Function grades Tier C — weak evidence. Effective, but with safety or population caveats.
C 🟠 C Weak Evidence Published with Warning
Why this grade7-layer evidence engine
⚖️
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditableRaw score 0.63
D
C
B
A
S
← counter-evidence / ineffectiveeffective / strong evidence →
Final grade
C · Published with Warning
Confidence
74%
Broadly consistent
Evidence level
E10
Mechanism / case reports / no human evidence
▸View the full decision path (audit trail)
- compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.626
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 僅有 E10 級證據 (cohort/animal/mechanism)，不足以下結論
- apply_hec_override — HEC-4 僅低階證據 (E8-E10) — 強制由 B 改為 U
- tier_strict_requirement_check — Tier 條件達標，未降階
- detect_disputes — 偵測到 0 個 hard + 0 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status
PubMed studies (5)L2 · primary research & systematic reviews
Copper and immunity
Finding: Reviewed evidence shows even marginal copper deficiency in humans causes (1) decreased neutrophil number (neutropenia is an early clinical sign), (2) decreased neutrophil bactericidal capacity that does not normalize with repletion of cell numbers alone, (3) reduced IL-2 production and T-cell proliferation to mitogens; immune defects precede biochemical changes in ceruloplasmin/SOD and reverse with oral copper repletion (2-3 mg/day)
View on PubMed Effects of low-copper diets on human immune response (Kelley DS et al., Am J Clin Nutr)
Finding: Low-copper diet (0.38 mg/day) significantly decreased the proliferative response of mononuclear cells to PHA and the proportion of IL-2 receptor-positive cells vs the adequate (2.49 mg/day) repletion period; immune indices changed before plasma copper/ceruloplasmin became overtly abnormal, indicating immune cells are a sensitive functional marker of marginal copper status
View on PubMed Long-term high copper intake: effects on indexes of copper status, antioxidant status, and immune function in young men
Finding: Neither moderately high (7.8 mg/day) nor low (0.7 mg/day) copper intake produced large changes in standard immune indices over 6 weeks in healthy men; some indices (e.g., percentage of IL-2R+ cells) trended lower at the low-copper phase but did not reach the magnitude seen in longer-duration depletion studies, suggesting immune effects require either deeper or longer copper restriction than 6 weeks at 0.7 mg/day
View on PubMed The immune system as a physiological indicator of marginal copper status?
Finding: Concluded that copper is essential for multiple arms of the immune response (neutrophil microbicidal activity via Cu/Zn-SOD and cytochrome c oxidase; T-helper cytokine balance; IL-2 production) and that experimentally induced human copper deficiency consistently produces neutropenia and reduced T-cell proliferation reversible with repletion; however, no benefit is demonstrated for copper supplementation above adequacy in copper-replete adults
View on PubMed Copper deficiency, a new triad: anemia, leucopenia, and myeloneuropathy
Finding: Acquired copper deficiency (post-bariatric surgery, excess zinc supplementation, malabsorption) commonly presents with neutropenia and increased susceptibility to infection; oral copper repletion (2-8 mg elemental/day) reliably reverses haematological abnormalities including neutrophil count and function within weeks, supporting a causal role of copper in granulopoiesis and innate immunity
View on PubMed Regulatory & authoritative positionsL4/L5 · FDA / EMA / NIH ODS / Cochrane / Mayo …
L4a US FDA
Supportive
Copper ... 0.9 mg source↗
L4b EU EFSA
Supportive
contributes to maintenance of normal connective tissues; contributes to normal functioning of the nervous system; contributes to normal cognitive function source↗
L4c UK NHS
Cautious
You should be able to get all the copper you need by eating a varied and balanced diet. source↗
L4d TW TFDA / 衛福部
Supportive
形態屬膠囊狀、錠狀且標示有每日食用限量之食品，在每日食用量中，其銅含量不得高於8毫克。限於補充食品中不足之營養素時使用。 source↗
L4e WHO
Neutral
A health-based guideline value of 2 mg/litre has been derived for copper in drinking-water... Copper is both an essential nutrient and a drinking-water contaminant. source↗
L5a NIH Office of Dietary Supplements
Supportive
Copper, an essential mineral, is naturally present in some foods and is available as a dietary supplement. It is a cofactor for several enzymes (known as 'cuproenzymes') involved in energy production, iron metabolism, neuropeptide activation, connective tissue synthesis, and neurotransmitter synthesis. source↗
L5b Mayo Clinic
Supportive
L5c Cleveland Clinic
Cautious
If your copper levels are too low, your immune system can't protect you from bacteria and other invaders. source↗