AUTHOR=Magriplis Emmanuella , Smiliotopoulos Theodoros , Myrintzou Niki , Burton-Pimentel Kathryn Jane , Adamberg Signe , Adamberg Kaarel , Agagündüz Duygu , Atanasova-Pancevska Natalijam , Beglaryan Meline , Brolsma Elske M. Brouwer , Burtscher Johana , Cerjak Marija , Ciesarová Zuzana , Ciprovica Inga , De Filippis Francesca , Gandía Mónica , Hillesheim Elaine , Hoxha Luziana , Borch Ibsen Daniel , Ivanova Nastia , Jenssen Håvard , Jones Petra , Kalea Anastasia , Kalyoncu Atasoy Zeynep Begum , Kitryte-Syrpa Vaida , Kostic Aleksandar , Laranjo Marta , Meslier Victoria , Nagybákay Nóra Emilia , Nakov Gjore , Nikola Malviina , Pafilas Christos , Papademas Photis , Pavli Foteini , Pitsi Tagli , Pohjanheimo Terhi , Pravst Igor , Rajic Jelena , Russo Pasquale , Sar Taner , Starowicz Małgorzata , Taljic Irzada , Trajkovska Biljana , Vergères Guy , Vidovic Bojana , Chassard Christophe , Syrpas Michail 

TITLE=Validation of the fermented food frequency questionnaire to assess consumption across four European regions: a study within the promoting innovation of fermented foods cost action

JOURNAL=Frontiers in Nutrition

VOLUME=Volume 12 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2025.1667653

DOI=10.3389/fnut.2025.1667653

ISSN=2296-861X

ABSTRACT=BackgroundFermented foods are an integral part of diets worldwide, and emerging epidemiological data suggest their significant beneficial health effects. However, assessing their intake is challenging since many of these foods are sporadically and/or locally consumed, hence current traditional nutritional assessment tools lack the specificity to capture this variability. To address this gap, the Fermented Food Frequency Questionnaire (3FQ) was developed and this study aimed to evaluate its relative validity and repeatability across European regions.MethodsIn the validation study of the 3FQ, 12,646 adult participants were recruited across four European regions to assess consumption of sixteen major fermented food groups. Repeatability was assessed by administering the 3FQ twice, ~6 weeks apart, to a subset of participants (n = 2,315). Validity was evaluated using 24-h dietary recalls (24 h). Statistical analyses included Spearman's rank correlation coefficients and Intra-Class Correlation coefficients (ICC) for repeatability, and Bland-Altman plots for validity.ResultsResults showed high repeatability, overall and by region, for estimated quantities and frequencies of consumption for most of the fermented food groups (from 0.4 to 1.0), with a few exceptions for infrequently consumed items (e.g., fermented fish). Validity assessment via Bland-Altman plots revealed excellent agreement between the 3FQ and 24 h for most of the food groups, with over 90% of values falling within the agreement interval. Notably, fermented dairy products, coffee, and bread categories showed the strongest agreement (>95%).ConclusionThe 3FQ is a robust and reliable tool for estimating the consumption of diverse fermented food groups across four European regions and provides valid estimates of the frequency and quantity of intake for specific fermented foods. The 3FQ could be a valuable instrument for epidemiological research aiming to elucidate associations between certain fermented foods and health parameters in European diets.