Skip to main content
ARS Home » Northeast Area » Beltsville, Maryland (BHNRC) » Beltsville Human Nutrition Research Center » Food Composition and Methods Development Laboratory » Research » Publications at this Location » Publication #328952

Title: Importance of accurate measurements in nutrition research: dietary flavonoids as a case study

Author
item Harnly, James - Jim

Submitted to: Advances in Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/4/2016
Publication Date: 6/4/2016
Citation: Harnly, J.M. 2016. Importance of accurate measurements in nutrition research: dietary flavonoids as a case study. Advances in Nutrition. 7:375-382.

Interpretive Summary: Accurate measurements of the secondary metabolites in natural products and plant foods are critical to establishing diet/health relationships. There are as many as 50,000 secondary metabolites which may influence human health. Their structural and chemical diversity present a challenge to analytical chemistry. With respect to flavonoids, putative identification is accessible, put positive identification and quantification are limited by the lack of standards. Quantification has been tested using non-specific and specific methods. Non-specific methods, which include antioxidant capacity methods, fail to provide information on the measured components, suffer from numerous interferences, are not equatable with each other, and are unsuitable for health research. Specific methods, such as liquid chromatography with diode array and mass spectrometric detection, require the use of internal standards and molar relative response factors. These methods are relatively expensive, require a high level of expertise, and require experimental verification. However, these methods represent the only suitable means of relating health outcomes to specific dietary components.

Technical Abstract: Accurate measurements of the secondary metabolites in natural products and plant foods are critical to establishing diet/health relationships. There are as many as 50,000 secondary metabolites which may influence human health. Their structural and chemical diversity present a challenge to analytical chemistry. With respect to flavonoids, putative identification is accessible, put positive identification and quantification are limited by the lack of standards. Quantification has been tested using non-specific and specific methods. Non-specific methods, which include antioxidant capacity methods, fail to provide information on the measured components, suffer from numerous interferences, are not equatable with each other, and are unsuitable for health research. Specific methods, such as liquid chromatography with diode array and mass spectrometric detection, require the use of internal standards and molar relative response factors. These methods are relatively expensive, require a high level of expertise, and require experimental verification. However, these methods represent the only suitable means of relating health outcomes to specific dietary components.