SynthesisNutrition journal2007
Is plasma vitamin C an appropriate biomarker of vitamin C intake? A systematic review and meta-analysis.
Synthesis in Nutrition journal, 2007. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 57 papers, 8 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
57 citing papers in PubMed, 8 syntheses or guidelines pooled it, 109 citations in OpenAlex.
- Pooled it
- Effect of Dietary or Supplemental Vitamin C Intake on Vitamin C Levels in Patients with and without Cardiovascular Disease: A Systematic Review.Nutrients · 2021Pooled it
- Dietary and circulating vitamin C, vitamin E, β-carotene and risk of total cardiovascular mortality: a systematic review and dose-response meta-analysis of prospective observational studies.Public health nutrition · 2019Pooled it
- Dietary Antioxidants, Circulating Antioxidant Concentrations, Total Antioxidant Capacity, and Risk of All-Cause Mortality: A Systematic Review and Dose-Response Meta-Analysis of Prospective Observational Studies.Advances in nutrition (Bethesda, Md.) · 2018Pooled it
- Pooled it
- Diet and risk of diabetic retinopathy: a systematic review.European journal of epidemiology · 2018Pooled it
- Vitamin C Status and Cognitive Function: A Systematic Review.Nutrients · 2017Pooled it
- The plasma level of retinol, vitamins A, C and α-tocopherol could reduce breast cancer risk? A meta-analysis and meta-regression.Journal of cancer research and clinical oncology · 2015Pooled it
- Vitamin C decreases reduced glutathione in chronic haemodialysis patients: a pilot, randomised, double-blind trial.International urology and nephrology · 2021Trial
- Relative Validity and Reproducibility of a Short FoodFrequency Questionnaire to Assess Nutrient Intakesof New Zealand Adults.Nutrients · 2020Trial
- The effect of 'Zesy002' kiwifruit (Journal of nutritional science · 2019Trial
- Combining vitamin C and carotenoid biomarkers better predicts fruit and vegetable intake than individual biomarkers in dietary intervention studies.European journal of nutrition · 2016Trial
- Human skeletal muscle ascorbate is highly responsive to changes in vitamin C intake and plasma concentrations.The American journal of clinical nutrition · 2013Trial
- Dietary vitamin C intake and the risk of islet autoimmunity and type 1 diabetes: The Environmental Determinants of Diabetes in the Young (TEDDY) Study.European journal of nutrition · 2026Observational
- A Narrative Review of Candidate Biomarkers of Total Fruit and Vegetable Intake.Nutrition bulletin · 2026Review
- Associations between serum biomarkers of fruit and vegetable intake and all-cause, cancer and CVD mortality among US adults.The British journal of nutrition · 2025Article
- Impact of vitamin C deficiency on imaging patterns and ventilatory function in pulmonary tuberculosis.Frontiers in medicine · 2025Article
- The relationship between serum vitamin C levels and high-sensitivity C-reactive protein in children.Scientific reports · 2024Article
- Association between Dietary Potassium Intake and Nonalcoholic Fatty Liver Disease and Advanced Hepatic Fibrosis in U.S. Adults.International journal of endocrinology · 2024Article
- Associations of serum vitamin C concentrations with risk of all-cause and cause-specific mortality among individuals with and without type 2 diabetes.European journal of nutrition · 2023Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundAs the primary source of dietary vitamin C is fruit and to some extent vegetables, the plasma level of vitamin C has been considered a good surrogate or predictor of vitamin C intake by fruit and vegetable consumption. The purpose of this systematic review was to investigate the relationship between dietary vitamin C intakes measured by different dietary methods and plasma levels of vitamin C.
methodWe searched the literature up to May 2006 through the OVID interface: MEDLINE (from 1960) and EMBASE (from 1988). We also reviewed the reference lists in the articles, reviews, and textbooks retrieved. A total of 26 studies were selected and their results were combined using meta-analytic techniques with random-effect model approach.
resultsThe overall result of this study showed a positive correlation coefficient between Food Frequency Questionnaire (FFQ) and biomarker (r = 0.35 for "both" genders, 0.39 for females, and 0.46 for males). Also the correlation between Dietary Recalls (DR)/diary and biomarker was 0.46 for "both" genders, 0.44 for females, and 0.36 for males. An overall correlation of 0.39 was found when using the weight record method. Adjusting for energy intake improved the observed correlation for FFQ from 0.31 to 0.41. In addition, we compared the correlation for smokers and non-smokers for both genders (FFQ: for non-smoker r = 0.45, adjusted for smoking r = 0.33).
conclusionOur findings show that FFQ and DR/diary have a moderate relationship with plasma vitamin C. The correlation may be affected/influenced by the presence of external factors such as vitamin bioavailability, absorption condition, stress and food processing and storage time, or by error in reporting vitamin C intake.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.