Association of plasma biomarkers of fruit and vegetable intake with incident type 2 diabetes: EPIC-InterAct case-cohort study in eight European countries
Authors: Zheng Ju-Sheng , Sharp Stephen J , Imamura Fumiaki , Chowdhury Rajiv , Gundersen Thomas E , Steur Marinka , Sluijs Ivonne , van der Schouw Yvonne T , Agudo Antonio , Aune Dagfinn , Barricarte Aurelio , Boeing Heiner , Chirlaque María-Dolores , Dorronsoro Miren , Freisling Heinz , El-Fatouhi Douae , Franks Paul W , Fagherazzi Guy , Grioni Sara , Gunter Marc J , Kyrø Cecilie , Katzke Verena , Kühn Tilman , Khaw Kay-Tee , Laouali Nasser , Masala Giovanna , Nilsson Peter M , Overvad Kim , Panico Salvatore , Papier Keren , Quirós J Ramón , Rolandsson Olov , Redondo-Sánchez Daniel , Ricceri Fulvio , Schulze Matthias B , Spijkerman Annemieke M W , Tjønneland Anne , Tong Tammy Y N , Tumino Rosario , Weiderpass Elisabete , Danesh John , Butterworth Adam S , Riboli Elio , Forouhi Nita G , Wareham Nicholas J 
Published: July 2020

Abstract

Objective
To investigate the association of plasma vitamin C and carotenoids, as indicators of fruit and vegetable intake, with the risk of type 2 diabetes.

Design
Prospective case-cohort study.

Setting
Populations from eight European countries.

Participants
9754 participants with incident type 2 diabetes, and a subcohort of 13 662 individuals from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort of 340 234 participants: EPIC-InterAct case-cohort study.

Main outcome measure
Incident type 2 diabetes.

Results
In a multivariable adjusted model, higher plasma vitamin C was associated with a lower risk of developing type 2 diabetes (hazard ratio per standard deviation 0.82, 95% confidence interval 0.76 to 0.89). A similar inverse association was shown for total carotenoids (hazard ratio per standard deviation 0.75, 0.68 to 0.82). A composite biomarker score (split into five equal groups), comprising vitamin C and individual carotenoids, was inversely associated with type 2 diabetes with hazard ratios 0.77, 0.66, 0.59, and 0.50 for groups 2-5 compared with group 1 (the lowest group). Self-reported median fruit and vegetable intake was 274 g/day, 396 g/day, and 508 g/day for participants in categories defined by groups 1, 3, and 5 of the composite biomarker score, respectively. One standard deviation difference in the composite biomarker score, equivalent to a 66 (95% confidence interval 61 to 71) g/day difference in total fruit and vegetable intake, was associated with a hazard ratio of 0.75 (0.67 to 0.83). This would be equivalent to an absolute risk reduction of 0.95 per 1000 person years of follow up if achieved across an entire population with the characteristics of the eight European countries included in this analysis.

Conclusions
These findings indicate an inverse association between plasma vitamin C, carotenoids, and their composite biomarker score, and incident type 2 diabetes in different European countries. These biomarkers are objective indicators of fruit and vegetable consumption, and suggest that diets rich in even modestly higher fruit and vegetable consumption could help to prevent development of type 2 diabetes.