Free fruit at workplace increases total fruit intake: a validation study using 24h dietary recall and urinary flavonoid excretion

Kirstine Suszkiewicz Krogholm (1) , Lea Bredsdorff (1) , Sevil Alinia (1) , Tue Christensen (1) , Salka Elbøl Rasmussen (1) , Lars Dragsted (1)

1 National Food Institute

Objective: To validate 24h dietary recall of fruit intake by measuring the total 24h excretion of ten different flavonoids in24h urine during an intervention with free fruit at workplaces. Design and methods: Employees at workplaces offering a free fruit program, consisting of daily free and easy access to fresh fruit, and controls employees at workplaces with no free fruit programme were enrolled in this validation study (n=103). Dietary intake was assessed by using a 24h dietary recall questionnaire at baseline and approximately 5 months later. Ten flavonoids, quercetin, isorhamnetin, tamarixetin, kaempferol, hesperetin, naringenin, eriodictyol, daidzein, genistein and phloretin, were measured using HPLC-electrospray ionisation-MS. Results: The 24h urinary excretion of total flavonoids and the estimated intake of fruits were significantly correlated (rs =0.31, p<0.01). The dietary intake of citrus fruits and citrus juices was significantly correlated with total excretion of citrus specific flavonoids (rs= 0.28, p<0.01), and orange was positively correlated with naringenin (rs=0.24, p<0.01) and hesperetin (rs=0.24, p<0.01). Phloretin in urine was correlated with apple intake (rs=0.22, p<0.01) and also with overall estimated intake of fruit (rs=0.22, p<0.01). Conclusion: The present study shows that a 24h dietary recall can be used as a valid estimate of the intake of fruits in agreement with an objective biomarker of fruit intake in free fruit at workplace interventions.

Mots clés: validation; biomarker; fruit; flavonoid; vegetables; 24h dietary recall questionaire

Kirstine Suszkiewicz Krogholm, Lea Bredsdorff, Sevil Alinia, Tue Christensen, Salka Elbøl Rasmussen, et al.. Free fruit at workplace increases total fruit intake: a validation study using 24h dietary recall and urinary flavonoid excretion. European Journal of Clinical Nutrition, 2010, ⟨10.1038/ejcn.2010.130⟩. ⟨hal-00563102⟩