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Published on: January 7, 2018
Fruit and vegetable intake and the association with glucose parameters: a cross-sectional analysis of the Let's
1Department of Cardiovascular Sciences, University of Leicester, Leicester, UK. Pc154@le.ac.uk
Background:
Dietary recommendations for the prevention of type 2 diabetes mellitus include the message to consume 400 g fruit and vegetables per day. Measurement of habitual diet is inherently difficult, yet errors due to self-report can be eliminated by the use of nutritional biomarkers. The aim of this study was to determine plasma vitamin C concentrations as a biomarker for fruit and vegetable intake in individuals identified at high risk of diabetes. Fruit and vegetables may confer benefit via their antioxidant capacity, thus we also measured urinary F₂-isoprostanes as a marker for oxidative stress.
Subjects/Methods:
Participants recruited from a high-risk population as part of a diabetes prevention trial provided fasting blood samples and a spot urine sample for the quantification of plasma vitamin C and F₂-isoprostanes, respectively. We compared glycaemic parameters by the increments of the standard deviation of plasma vitamin C using multiple regression models.
Results:
Mean plasma vitamin C of participants was 39.3 micromol/l (s.d. 21.8). In the unadjusted model, 1 s.d. plasma vitamin C was significantly and inversely associated with HbA1c, fasting and 2 h blood glucose (P ≤ 0.0001). Relationships remained significant after adjustment for demographic variables and confounding factors. No significant association was observed between plasma vitamin C and urinary F₂-isoprostanes.
Conclusion:
The data adds to the evidence that small lifestyle changes may influence glucose regulation. The role that fruit and vegetables independently have should be investigated further.
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