Vitamin C for Wound Healing
Verdict: Published
Across 6 PubMed studies, the evidence for Vitamin C in Wound Healing grades Tier A — moderate evidence.
A 🔵 A Moderate Evidence Published
Why this grade7-layer evidence engine
⚖️
Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditableRaw score 0.57
D
C
B
A
S
← counter-evidence / ineffectiveeffective / strong evidence →
Final grade
A · Published
Confidence
89%
Highly consistent evidence
Evidence level
E1
Cochrane high-quality SR/MA
▸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 = 0.575
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 無高階證據可裁決
- 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 (6)L2 · primary research & systematic reviews
Nutritional interventions for preventing and treating pressure ulcers
Finding: Across 33 RCTs (7,920 participants) the evidence was very uncertain about the effect of vitamin C on pressure ulcer healing, based on only 1-2 small trials and rated very low-certainty (no reliable pooled estimate could be derived).
View on PubMed Randomized clinical trial of ascorbic acid in the treatment of pressure ulcers
Finding: High-dose vitamin C (500 mg twice daily vs 10 mg twice daily) did NOT speed pressure-ulcer healing (closure hazard ratio 0.78, 90% interval 0.44-1.39; mean healing 0.21 vs 0.27 cm2/week, both favouring control).
View on PubMed A Systematic Review on the Role of Vitamin C in Tissue Healing
Finding: Of 18 included studies, vitamin C improved healing mainly for pressure ulcers, but the authors stressed most studies had small samples, used combined nutrients and did not test baseline vitamin C status, so no pooled effect was estimated.
View on PubMed Vitamin C improves healing of foot ulcers: a randomised, double-blind, placebo-controlled trial
Finding: In 16 patients with diabetic foot ulcers, 8-week healing was significantly greater with vitamin C than placebo (median 100% vs -14%, P=0.041), but the trial was very small and underpowered.
View on PubMed Treatment with supplementary arginine, vitamin C and zinc in patients with pressure ulcers: a randomised controlled trial
Finding: A combined arginine + vitamin C + zinc supplement improved PUSH scores (8.7 to 2.6 by week 3, P<0.01) versus no improvement in controls, but vitamin C cannot be isolated because three nutrients were given together.
View on PubMed Efficacy of vitamin C supplementation in preventing and treating complex regional pain syndrome type I (CRPS-I) in Orthopedic patients: A systematic review and meta-analysis
Finding: Pooling 8 studies, vitamin C trended toward lower CRPS-I incidence but the pooled effect was NOT statistically significant (I2=26.28%, p=0.22) and publication bias was detected.
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, also known as vitamin C, is necessary for wound healing. It is needed for many functions in the body, including helping the body use carbohydrates, fats, and protein. It also strengthens blood vessel walls. source↗
L5c Cleveland Clinic
Supportive
Vitamin C helps your body produce collagen, which is essential for skin repair and wound healing. Collagen is a protein that's key to properly healing wounds, including cuts, scrapes and surgical incisions. source↗
L5d Harvard Health
Supportive
Vitamin C plays a key role in creating collagen, a protein essential for maintaining healthy skin, tendons, ligaments, and blood vessels, as well as for repairing wounds and forming scar tissue. source↗
L5e Specialty Society (condition-mapped)
Supportive
Vitamin C is an antioxidant that reduces free-radical damage in cells, boosts immunity and is required for the synthesis of collagen. There is no evidence that mega doses of ascorbic acid accelerate wound healing unless the person is deficient. Taking more than 2,000 milligrams daily for a prolonged period of time can result in nausea or diarrhea. source↗