Colostrum for Immune Function
Bovine colostrum shows a modest signal for reducing upper-respiratory infections in heavily-stressed or high-exposure groups (athletes, exposed students, young children), but it does not reliably move immune blood markers and is not a proven immune booster for healthy adults. Major regulators and clinics do not endorse it for immune function.
Why this grade7-layer evidence engine
The grade is Weak Evidence (Tier C) because the clinical and biological data point in different directions. Two meta-analyses found fewer upper-respiratory infections with colostrum: a 2016 analysis in exercising adults (PMID 27462401, n=152) reported 44% fewer symptom-days and 38% fewer episodes, and a 2022 analysis (PMID 37111143, n=445, 7 trials) found a risk ratio of 0.64. But 4 of 5 trials in the 2016 review were at moderate-to-high risk of bias, keeping confidence limited.
Crucially, a 2020 meta-analysis of immune blood markers (PMID 32276466, n=239, industry-funded by Nutricia) found little to no effect on serum IgA, IgG, lymphocytes or neutrophils, so the mechanism behind any benefit is unclear. The clinical effect also appears confined to specific groups: a 2023 trial (PMID 37111143, n=158) helped only the high-exposure medical-student subgroup, and a positive pediatric trial (PMID 37630816) was very small (n=57). Generalizing to ordinary healthy adults is not supported.
Regulators and clinics reinforce the cautious grade rather than overturn it. The US FDA treats disease-claim colostrum products as unapproved new drugs that are not generally recognized as safe and effective, the EU's EFSA rejected colostrum immune-defence claims as having no established cause-and-effect, and WHO/WADA flag trace IGF-1 for athletes. Cleveland Clinic advises against it, and Mayo Clinic notes benefits mostly in elite athletes. Net result: a real but narrow, low-certainty signal, not a broad immune cure.
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditable▸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 = 0.455
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 高品質 SR/MA 顯示 positive (2 篇 > 0 negative)
- tier_strict_requirement_check — Tier 條件達標，未降階
- detect_disputes — 偵測到 0 個 hard + 1 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status