Vitamin C for Scurvy
Verdict: Published with Warning
Across 5 PubMed studies, the evidence for Vitamin C in Scurvy grades Tier A — moderate evidence. Effective, but with safety or population caveats.
A 🔵 A Moderate Evidence Published with Warning
Why this grade7-layer evidence engine
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Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditableRaw score 0.76
D
C
B
A
S
← counter-evidence / ineffectiveeffective / strong evidence →
Final grade
A · Published with Warning
Confidence
94%
Highly consistent evidence
Evidence level
E2
Multiple high-quality MAs (≥2 independent, consistent)
▸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 = 0.76
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 高品質 SR/MA 顯示 positive (1 篇 > 0 negative)
- 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
Bleeding tendency and ascorbic acid requirements: systematic review and meta-analysis of clinical trials
Finding: Pooling 15 controlled trials (n=1140), ascorbic acid supplementation significantly reduced gingival bleeding tendency when baseline plasma AA was <28 umol/L (SMD -0.83, 95%CI -1.16 to -0.49, P<0.002), and in NHANES III (n=8210) both gingival bleeding (PR 1.64, 95%CI 1.32-2.03) and retinal haemorrhage (PR 1.47, 95%CI 1.22-1.77) were more prevalent at the low plasma levels (11-28 umol/L) that merely prevent overt scurvy.
View on PubMed Vitamin C pharmacokinetics in healthy volunteers: evidence for a recommended dietary allowance
Finding: In a controlled in-hospital depletion-repletion dose-escalation study (7 men on <5 mg/day then escalating doses), plasma vitamin C rose sigmoidally; the steep deficiency-correcting portion lay between 30 and 100 mg/day, cells saturated at 100 mg/day and plasma at 1000 mg/day, leading the authors to raise the recommended dietary allowance from 60 to 200 mg/day (no comparative p-value; within-subject dose-response).
View on PubMed A new recommended dietary allowance of vitamin C for healthy young women
Finding: A companion in-hospital depletion-repletion dose-escalation study in healthy young women (hospitalised 186+/-28 days, doses 30-2500 mg/day) reproduced the sigmoidal dose-plasma relationship with plasma and cell saturation at 400 mg/day, supporting an increase of the women's RDA to 90 mg/day; F2-isoprostane oxidant-stress markers were unchanged across all doses (within-subject dose-response, no comparative p-value).
View on PubMed A Narrative Review on Pediatric Scurvy: The Last Twenty Years
Finding: Structured review of 15 articles reporting 166 children with scurvy found the disease re-emerging in children with restrictive diets or neurodevelopmental disability, frequently misdiagnosed as autoimmune/infectious/neoplastic disease, with serum vitamin C as diagnostic gold standard and clinical resolution following vitamin C repletion (descriptive case series, no comparator or effect estimate).
View on PubMed Scurvy: old disease, new lessons
Finding: Narrative clinical review confirming scurvy is caused by severe vitamin C deficiency and is fully reversible with vitamin C replacement, with symptoms resolving rapidly on treatment; it stresses that scurvy is a present-day disease in at-risk groups (autism spectrum disorder, restricted diets) and is often diagnostically delayed (descriptive, no comparator or effect estimate).
View on PubMed Regulatory & authoritative positionsL4/L5 · FDA / EMA / NIH ODS / Cochrane / Mayo …
L4a US FDA
Supportive
Consumption of antioxidant vitamins may reduce the risk of certain kinds of cancer. source↗
L4b EU EFSA
Supportive
A cause and effect relationship has been established between the dietary intake of vitamin C and protection of DNA, proteins and lipids from oxidative damage. source↗
L4c UK NHS
Cautious
You should be able to get all the vitamin C you need by eating a varied and balanced diet. If you take vitamin C supplements, do not take too much as this could be harmful. source↗
L4d TW TFDA / 衛福部
Supportive
成人每日需要的攝取量為100毫克、孕婦每日120毫克、哺乳媽媽每日140毫克 source↗
L4e WHO
Neutral
Vitamin E and C supplementation is not recommended for pregnant women to improve maternal and perinatal outcomes. source↗
L5a NIH Office of Dietary Supplements
Supportive
Vitamin C plays an important role in immune function and improves the absorption of nonheme iron. source↗
L5b Mayo Clinic
Supportive
Ascorbic acid injection is used to treat scurvy (Vitamin C deficiency) in patients who cannot take the medicine by mouth, and is used for short term treatment (up to 1 week) only. For oral treatment, the recommended dose for scurvy is 100 to 300 mg a day for at least 2 weeks. Not having enough vitamin C can lead to a condition called scurvy, which causes anemia, bleeding gums, bruising and poor… source↗
L5c Cleveland Clinic
Supportive
The condition is easily treatable by consuming more vitamin C. You should try to maintain a nutritious diet that includes one to two times your daily recommended amount of vitamin C. Children with scurvy can take a supplement of up to 300 milligrams (mg) daily. Adults can take between 500 mg and 1000 mg. Most people feel better within 48 hours of treatment. You should be able to make a full rec… source↗
L5d Harvard Health
Supportive
Increased bleeding in general is one of the symptoms of scurvy, a disease caused by severe vitamin C deficiency. Scurvy, which often affected 18th-century sailors without access to fruits and vegetables, is rare today. The experts also suggest increasing your vitamin C for good measure, by eating more foods like kale, oranges, peppers, and kiwis, or from a daily 100-mg to 200-mg vitamin C suppl… source↗
L5e Specialty Society (condition-mapped)
Supportive
Treatment of scurvy with vitamin C replacement is curative. Treatment with vitamin C includes dosages up to 300 mg/d for children and 500 to 1000 mg/d for adults for 1 month. An alternative adult regimen is up to 2 g/d for the initial 3 days, 500 mg/d for 1 week, and 100 mg/d for 1 to 3 months. The end point of replacement typically occurs within 1 to 3 months or upon the complete resolution of… source↗