It is the first time that a scientific study associates high polyphenols intake with a 30% reduction in mortality in older adults. The research, published on Journal of Nutrition, is the first to evaluate the total dietary polyphenol intake by using a nutritional biomarker and not only a food frequency questionnaire. Research is signed by Cristina Andrés Lacueva, Montserrat Rabassa and Mireia Urpí Sardà, from the Department of Nutrition and Bromatology of the UB; Raúl Zamora Ros (ICO-IDIBELL), and experts Antonio Cherubini (Italian National Research Centre on Aging), Stefania Bandinelli (Azienda Sanitaria di Firenze, Italy) and Luigi Ferrucci (National Institute on Ageing, United States).
Polyphenols are naturally occurring compounds found largely in fruits, vegetables, coffee, tea, nuts, legumes and cereals. More than 8,000 different phenolic compounds have been identified in plants. Polyphenols have antioxidant, antiinflammatory, anticarcinogenic, etc. effects.
The research published on Journal of Nutrition is based on a 12-year follow-up of a population sample composed by 807 men and women aged 65 or over from Greve and Bagno (Tuscany, Italy), within the InCHIANTI study. The group of the UB analysed the effect of polyphenol-rich diets by means of a nutritional biomarker -- the total urinary polyphenol (TUP) concentration -- as a proxy measure of intake. To be exact, UB researchers contributes to first literature references on TUP application to epidemiological or clinical studies.
New biomarkers for nutritional studies
Professor Cristina Andrés Lacueva, head of the Biomarkers and Nutritional & Food Metabolomics Research Group of the UB and coordinator of the study, explains that "the development and use of nutritional biomarkers enables to make a more precise and, particularly, more objective estimation of intake as it is not only based on participants' memory when answering questionnaire. Nutritional biomarkers take into account bioavailabity and individual differences. According to the expert, "this methodology makes a more reliable and accurate evaluation of the association between food intake and mortality or disease risk."
In conclusion, the research proves that overall mortality was reduced by 30% in participants who had rich-polyphenol diets (>650 mg/day) in comparison with the participants who had low-polyphenol intakes (<500 mg/day).
Raúl Zamora Ros, first author of the study, points out that "results corroborate scientific evidence suggesting that people consuming diets rich in fruit and vegetables are at lower risk of several chronic diseases and overall mortality." Moreover, the research stresses the importance of evaluating -- if possible -- food intake by using nutritional biomarkers, not only food frequency questionnaires.
The Biomarkers and Nutritional & Food Metabolomics Research Group, which participates in the project Fun-C-Food (Consolider Ingenion), collaborates actively with several national and international research groups. It focuses its activity on the analysis of new more effective and sensitive nutritional biomarkers based on the bioavailabilty of bioactive compounds in food and their activity, in order to associate the intake of certain foods (consumption markers) with their potential effects on people's health.