The amounts of healthy substances in fruit and vegetable products vary somuch that the possible beneficial health effects from these products is farfrom optimal. Simulations done by researchers at Wageningen University predictabout a 45% reduction in the risk of colon cancer (2700 cases per year in theNetherlands) if the entire production chain can see to it that the averagequality of healthy substances in fruit and vegetable products increases bya factor of 3. Furthermore, the same products also have to vary much less withregard to the amount of health beneficial substances than the more than hundredfolddifferences which are currently found among products.
The health benefit seems realisable through the selection of fruit and vegetablevarieties, the optimalisation of the treatment process, and the provision ofgood consumer information, according to the researchers Matthijs Dekker anRuud Verkert from the chair group Product Design and Quality Management atWageningen University.
The Wageningen researchers analysed the entire production chain--from "theground to the mouth" --of both fresh vegetables and fruits as well asprocessed products such as juices and ready-made meals. In their research,Dekker and Verkert have mapped out what happens to important health promotingeffects such as glucosinolates.
According to the researchers, the breeding, cultivation, storage and processingof fruits and vegetables have always been aimed at maximizing production, minimizingloss from spoilage, and maintaining an attractive appearance of the fruitsand vegetables for the consumer. Fruits and vegetables, however, contain importantcomponents for human health such as vitamins and minerals. In the last years,it has also become clear that more plant substances such as flavonoids, carotenoids,and glucosinolates play an important protective role against all kinds of diseasesrelated to ageing, such as cancer, heart and vascular diseases. Furthermore,there have also been recent indications that these substances delay the processof dementia.
Numerous epidemiological studies on the relationship between the consumptionof fruits and vegetables and diseases related to ageing, in which data of,at times, thousands of people have been processed, turn out to be rather variable.In these studies, beneficial effects have been found but the effects also showlarge variation and strongly differ between studies . The enormous variationin the amounts in the consumed form of fruits and vegetables are a possibleexplanation for the health researchers' conflicting results.
Laboratory research into the effect of the health benefits of the variouscomponents from the fruits and vegetables shows much clearer effects. Also,animal experiments and human intervention studies give much more unequivocaleffects. In the experiments and studies, DNA damage , which is coupled to diseasesrelated to ageing, was looked at.
Production process
Several steps and choices in the production chain determine the amount of healthysubstances in the final product: the chosen fruit and vegetable varieties,the conditions of cultivation and post-harvest conditions of storage andprocessing, both industrially and in the consumer's kitchen. The variationis not visible to the consumer because these products do not have the amountsof these materials on their label.
Note for the editors
For more information, please contact Dr. Matthijs Dekker (chair group ProductDesign and Quality Management, Wageningen University), tel. +31.317483214or +31.644042486, email: matthijs.dekker@wur.nl. You may also contact RuudVerkerk, tel. +31.317483226 or +31.616550488, email: ruud.verkerk@wur.nl.