In order to establish firm evidence for the health effects of dietary polyphenol consumption, it is essential to have quantitative information regarding their dietary intake. The usefulness of the current methods, which rely mainly on the assessment of polyphenol intake using food records and food composition tables, is limited as they fail to assess total intake accurately. This review highlights the problems associated with such methods with regard to polyphenol-intake predictions. We suggest that the development of biological biomarkers, measured in both blood and urine, are essential for making accurate estimates of polyphenol intake. However, the relationship between dietary intakes and nutritional biomarkers are often highly complex. This review identifies the criteria that must be considered in the development of such biomarkers. In addition, we provide an assessment of the limited number of potential biomarkers of polyphenol intake currently available. In the last decade, there has been intense interest in the potential health benefits of dietary-derived plant polyphenols. An everincreasing number of studies have described their antioxidant properties and linked this to their proposed role in the prevention of human disease. Plant polyphenols are abundant in the human diet, particularly in fruit, vegetables and pulses which have been consistently associated with a decreased risk of cancer 1 -3 , CVD 4 -6 and a range of other chronic disorders. The likely active components of fruits, vegetables and pulses are a group of phytochemicals, known as polyphenols. However, it has proved extremely difficult to quantitatively establish the benefit afforded by polyphenols for a number of reasons: (1) there is a great diversity of polyphenol content between foods; (2) there is limited data regarding the polyphenol content of specific foods within the commonly-used food composition databases; (3) there are challenges in characterising and quantifying habitual food intake; and (4) there is a limited understanding regarding the extent of absorption and metabolic fate of individual polyphenols from particular foods.Biological markers of nutrient exposure, as an alternative to the more traditional dietary assessment tools, have been used for many years. In this approach one or more biochemical moieties are measured in an accessible fluid or tissue to provide a semi-quantitative index of the exposure to individual food constituents. For polyphenols, this may appear to be an attractive approach. However, the relationship between dietary intake and resulting concentrations of biomarkers in body fluids is highly complex. Before a particular dietary component, or its metabolite, can be used as a sensitive and accurate biomarker of exposure to a specific polyphenol, a number of factors must be realised. Firstly, a full understanding of the metabolism of polyphenols in human subjects is required in order to select credible biomarkers. Secondly, it is important to understand the time -response relationship between polyphenol int...

No abstract

No abstract

No abstract