Correlations between Fruit, Vegetables, Fish, Vitamins, and Fatty Acids Estimated by Web-Based Nonconsecutive Dietary Records and Respective Biomarkers of Nutritional Status

J Acad Nutr Diet. 2016 Mar;116(3):427-438.e5. doi: 10.1016/j.jand.2015.09.017. Epub 2015 Oct 27.


Background: It is of major importance to measure the validity of self-reported dietary intake using web-based instruments before applying them in large-scale studies.

Objective: This study aimed to validate self-reported intake of fish, fruit and vegetables, and selected micronutrient intakes assessed by a web-based self-administered dietary record tool used in the NutriNet-Santé prospective cohort study, against the following concentration biomarkers: plasma beta carotene, vitamin C, and n-3 polyunsaturated fatty acids.

Participants/setting: One hundred ninety-eight adult volunteers (103 men and 95 women, mean age=50.5 years) were included in the protocol: they completed 3 nonconsecutive-day dietary records and two blood samples were drawn 3 weeks apart. The study was conducted in the area of Paris, France, between October 2012 and May 2013.

Main outcome measures: Reported fish, fruit and vegetables, and selected micronutrient intakes and plasma beta carotene, vitamin C, and n-3 polyunsaturated fatty acid levels were compared.

Statistical analyses: Simple and adjusted Spearman's rank correlation coefficients were estimated after de-attenuation for intra-individual variation.

Results: Regarding food groups in men, adjusted correlations ranged from 0.20 for vegetables and plasma vitamin C to 0.49 for fruits and plasma vitamin C, and from 0.40 for fish and plasma c20:5 n-3 (eicosapentaenoic acid [EPA]) to 0.55 for fish and plasma c22:6 n-3 (docosahexaenoic acid). In women, correlations ranged from 0.13 (nonsignificant) for vegetables and plasma vitamin C to 0.41 for fruits and vegetables and plasma beta carotene, and from 0.27 for fatty fish and EPA to 0.54 for fish and EPA+docosahexaenoic acid. Regarding micronutrients, adjusted correlations ranged from 0.36 (EPA) to 0.58 (vitamin C) in men and from 0.32 (vitamin C) to 0.38 (EPA) in women.

Conclusions: The findings suggest that three nonconsecutive web-based dietary records provide reasonable estimates of true intake of fruits, vegetables, fish, beta carotene, vitamin C, and n-3 fatty acids. Along with other validation studies, this study shows acceptable validity of using such diet-assessment methods in large epidemiologic surveys and broadens new perspectives for epidemiology.

Keywords: Dietary record; Internet; Plasma biomarkers; Validation study.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Ascorbic Acid / administration & dosage
  • Ascorbic Acid / blood
  • Biomarkers / blood
  • Body Mass Index
  • Cholesterol, HDL / blood
  • Cholesterol, LDL / blood
  • Diet Records
  • Energy Intake
  • Fatty Acids, Omega-3 / administration & dosage*
  • Fatty Acids, Omega-3 / blood
  • Female
  • Fishes
  • France
  • Fruit*
  • Humans
  • Internet
  • Male
  • Micronutrients / administration & dosage
  • Micronutrients / blood
  • Middle Aged
  • Nutrition Assessment
  • Nutritional Status*
  • Prospective Studies
  • Reproducibility of Results
  • Seafood*
  • Vegetables*
  • Vitamins / administration & dosage*
  • Vitamins / blood
  • beta Carotene / administration & dosage
  • beta Carotene / blood


  • Biomarkers
  • Cholesterol, HDL
  • Cholesterol, LDL
  • Fatty Acids, Omega-3
  • Micronutrients
  • Vitamins
  • beta Carotene
  • Ascorbic Acid