Antioxidants in food: content, measurement, significance, action, cautions, caveats, and research needs

There are a multitude of antioxidants in foods, especially in foods of plant origin. Higher intake of antioxidant-rich foods is clearly associated with better health and functional longevity. The specific agents and mechanisms responsible are not yet clear, but there is convincing evidence that including more plant-based, antioxidant-rich foods, herbs, and beverages in the diet is effective in promoting health and lowering risk of various age-related diseases. The content of some individual antioxidants, such as vitamin C, in food can be measured, but it is not feasible to attempt to measure each antioxidant separately, and methods have been developed to assess the "total antioxidant content" of foods. One of the most widely used methods is the ferric reducing/antioxidant power (FRAP) assay, which is relatively simple, quick, sensitive, and inexpensive to perform. There are many published studies that have used the FRAP assay, and these have generated a very large database of total antioxidant content of foods that can help guide food choices for increased antioxidant intake. The FRAP assay has also been used to assess the bioavailability of antioxidants in foods and to investigate the effects of growing conditions, storage, processing, and cooking method on the total antioxidant content of food. The test can be employed as a quality control check device, and to detect adulteration of food. Furthermore, in a modified form (FRASC), the assay can measure ascorbic acid content almost simultaneously with the total antioxidant content of the sample. In this chapter, basic concepts of oxidation and the role of antioxidants, as well as the types and action of different antioxidants in foods will be reviewed briefly, and the underpinning concepts and evidence for health benefits of increased intake of dietary antioxidants will be discussed, with some focus on vitamin C, and also in the context of our evolutionary development. The basic concepts and limitations of measuring "total antioxidant content" of food will be presented. The FRAP assay and the modified version FRASC will be described, and the total antioxidant content (as the FRAP value) of a range of foods will be presented. Finally, issues of bioavailability and redox balance will be discussed in relation to the biological significance and molecular action of antioxidants in foods, some caution and caveats are presented about overcoming biological barriers to absorption of antioxidant phytochemicals, and research needs to further our understanding in the important area of food, antioxidants, and health will be highlighted. Content: Series Page Page ii Copyright Page iv Contributors Page vii Preface Page ix C.J. Henry Chapter One - Antioxidants in Food: Content, Measurement, Significance, Action, Cautions, Caveats, and Research Needs Pages 1-53 Iris F.F. Benzie, Siu-Wai Choi Chapter Two - Micronutrient Status in Type 2 Diabetes: A Review Pages 55-100 Bhupinder Kaur, Jeyakumar Henry Chapter Three - Sarcopenia and Nutrition Pages 101-136 Alessandro Laviano, Chiara Gori, Serena Rianda Chapter Four - Current Evidence on Dietary Pattern and Cognitive Function Pages 137-163 Bernice H.K. Cheung, Ivan C.H. Ho, Ruth S.M. Chan, Mandy M.M. Sea, Jean Woo Index Pages 165-169

Advances in Food and Nutrition Research recognizes the integral relationship between the food and nutritional sciences and brings together outstanding and comprehensive reviews that highlight this relationship. Contributions detail scientific developments in the broad areas of food science and nutrition and are intended to provide those in academia and industry with the latest information on emerging research in these constantly evolving sciences.

*The latest important information for food scientists and nutritionists *Peer-reviewed articles by a panel of respected scientists *The go-to series since 1948

Advances in Food and Nutrition Research recognizes the integral relationship between the food and nutritional sciences and brings together outstanding and comprehensive reviews that highlight this relationship. Contributions detail scientific developments in the broad areas of food science and nutrition and are intended to provide those in academia and industry with the latest information on emerging research in these constantly evolving sciences. *The latest important information for food scientists and nutritionists *Peer-reviewed articles by a panel of respected scientists *The go-to series since 1948