Vitamin C

Tier-BPublic-ready6/28/2026

Glucose and metabolic health markers is closer to a research marker, so it should be read separately from a directly felt benefit.

The 60.0 score includes research signals from patient or disease contexts. General supplement evidence is not repeated enough, so the B tier remains conservative.

Representative tier calculated from paper evidence that passed the collection audit.

Papers analyzed

101

Caution signal

Low

Context-specific research signal

60.0

Glucose and metabolic health markersBlood-Level or Deficiency MarkerCholesterol and triglycerides

Main benefit evidence

The representative ingredient tier is calculated from these target-level evidence groups.

Glucose and metabolic health

6 studiesTier-B

Glucose and metabolic health markers

Fairly consistent positive signal in studiesResearch marker focusPatient-group study

This card is closer to a measured biomarker or lab outcome than a directly felt user benefit. These findings come from a defined study population, so everyday effects may differ.

Evidence score

58.5

Study context

Patient-group study

This score reflects the strength of this benefit group. The ingredient tier also considers paper count, repetition, population, and study context.

Nutrient status and deficiency

4 studiesTier-B

Blood-Level or Deficiency Marker

Fairly consistent positive signal in studiesResearch marker focusPatient-group study

This is based on lab markers such as blood levels, deficiency correction, or absorption. Read it separately from directly felt outcomes.

Evidence score

54.6

Study context

Patient-group study

This score reflects the strength of this benefit group. The ingredient tier also considers paper count, repetition, population, and study context.

Blood lipids

4 studiesTier-B

Cholesterol and triglycerides

Fairly consistent positive signal in studiesFelt benefit focusPatient-group study

Potential benefit studied in Blood lipids. These findings come from a defined study population, so everyday effects may differ.

Evidence score

54.6

Study context

Patient-group study

This score reflects the strength of this benefit group. The ingredient tier also considers paper count, repetition, population, and study context.

Immune and respiratory health

2 studiesTier-C

Immune and respiratory support

Fairly consistent positive signal in studiesFelt benefit focusPatient-group study

Potential benefit studied in Immune and respiratory health. These findings come from a defined study population, so everyday effects may differ.

Evidence score

48.7

Study context

Patient-group study

This score reflects the strength of this benefit group. The ingredient tier also considers paper count, repetition, population, and study context.

Bone and joint health

1 studiesTier-C

Bone, joint, and mobility

Some positive signal observedFelt benefit focusPatient-group study

Potential benefit studied in Bone and joint health. These findings come from a defined study population, so everyday effects may differ.

Evidence score

42.7

Study context

Patient-group study

This score reflects the strength of this benefit group. The ingredient tier also considers paper count, repetition, population, and study context.

Blood pressure and vascular health

1 studiesTier-C

Blood pressure and vascular health markers

Some positive signal observedResearch marker focusPatient-group study

This card is closer to a measured biomarker or lab outcome than a directly felt user benefit. These findings come from a defined study population, so everyday effects may differ.

Evidence score

22.8

Study context

Patient-group study

This score reflects the strength of this benefit group. The ingredient tier also considers paper count, repetition, population, and study context.

Recent research

Updated This Month10 new papers

Observed range in repeated studies

This range includes studies in specific patient groups. It is not a general dose or recommendation.

Lower observed study value

mg/day

13 independent studies

Higher observed study value

3000

mg/day

Only ranges repeated in human, oral, single-ingredient studies are shown.

Not personal dosing instructions, recommendations, or safety limits.

Side effects and combination findings in studies

Findings from studies of this ingredient alone are separated from findings involving another supplement or medication.

Caution index

0.8

Caution band: Low

Caution signals

Side effects + combos + curated rules

Key precautions

No curated contraindication rule is available yet, but literature caution signals are shown below.

1 combo signals and 0 added-signal combos shown below.

These are signals reported in studies. They do not predict what will happen to an individual.

Findings to review with care

Side effects reported for the ingredient alone are separated from findings involving another supplement or medication.

Side effects reported when this ingredient was used alone

Symptoms or adverse events reported in studies of this ingredient without another active ingredient.

Adverse effect signal1 papers

High-dose vitamin C therapy has been reported to cause secondary calcium oxalate nephropathy, worsen acute kidney injury, and delay renal recovery in non-burn patients, and a case series in burn patients identified calcium oxalate nephropathy after high-dose vitamin C therapy.Human studies · Study type not identified

Adverse effect signal1 papers

High-dose vitamin C supplementation is reported to increase urinary oxalate, which may increase the risk of hyperoxaluria and oxalate kidney stones.Human studies · Study type not identified

Adverse effect signal1 papers

Contraindications for high-dose ascorbic acid are mentioned, including calcium oxalate urolithiasis, phenylketonuria, primary hemochromatosis, G6PD deficiency, and thalassemia.Human studies · Study type not identified

Adverse effect signal1 papers

High-dose ascorbic acid is reported to increase serotonin via tryptophan hydrolysis, which may cause sensitization to pain through pro-nociceptive serotonin receptors.Human studies · Study type not identified

Adverse effect signal1 papers

Calcium ascorbate EC showed better tolerability and fewer epigastric adverse events compared to ascorbic acid.Human studies · Study type not identified

Positive combinations studied

Positive combination findings are separated by how the study compared the groups. This is not a recommendation to combine them.

Positive findings when used together

The combination had a positive result, but the contribution of each ingredient could not be separated.

비타민 EIn a triple-blind RCT of 60 women with endometriosis, daily supplementation with 1000 mg Vitamin C and 800 IU Vitamin E for 8 weeks significantly reduced pelvic pain, dysmenorrhea, and dyspareunia (p < 0.001) compared to placebo.

Evidence summaries

Paper IDs and full lists are private. Only study types and summaries are shown.

Key Evidence #1

Public scholarly dataCitation signal: 448

review

The current evidence for the use of vitamin C and quercetin both for prophylaxis in high-risk populations and for the treatment of COVID-19 patients as an adjunct to promising pharmacological agents such as Remdesivir or convalescent plasma is presented.

Key Evidence #2

Public scholarly dataCitation signal: 291

review

The L-enantiomer of ascorbic acid, commonly known as vitamin C, is an indispensable nutrient and plays a key role in retaining the physiological process of humans and animals and its interaction with coexisting components.

Key Evidence #3

Public scholarly dataCitation signal: 259

observational

The data suggest that L-galactose-1-phosphate phosphatase could play an important role in regulating ascorbic acid accumulation during tomato fruit development and ripening, and the hypoxic and post-anoxic response in tomato fruit are discussed.

3 more summariesLimited representative sample by study type.

Public scholarly dataCitation signal: 257

review

In this review, the multiple roles of vitamin C in plant physiology as well as the regulation of its content, through biosynthetic or recycling pathways, are analyzed and attention is paid to the strategies that have been used to increase the content of vitami

Public scholarly dataCitation signal: 191

observational

Supplemental vitamin C to pregnant smokers improved newborn PFTs and decreased wheezing through 1 year in the offspring and may be an inexpensive and simple approach to decrease the effects of smoking in pregnancy on newborn pulmonary function and respiratory

Public scholarly dataCitation signal: 189

review

The available evidence indicates that vitamin C hypovitaminosis and deficiency is common in low- and middle-income countries and not uncommon in high income settings, and suggests a need for interventions to prevent deficiency in a range of at risk groups and

Vitamin C

Evidence score: 60.0|Caution index: 0.8

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