Changes in Antioxidant Capacity

Antioxidant capacity of the blood may be one indicator of a food's ability to act as an in vivo antiox-idant. Two commonly used measures of overall antioxidant capacity are the ORAC assay (oxygen radical absorbance capacity) and the FRAP assay (ferric reducing ability of plasma). Dietary interventions do alter the antioxidant capacity of blood. For example, individuals consuming a high cocoa and chocolate diet for 2 weeks have higher serum ORAC than when they consume a control diet. However, these results are not always consistent. For example, in individuals consuming pro-cyanidins in similar amounts of cocoa powder and chocolate, there is no change in plasma ORAC after 6 or 12 weeks.

Green tea consumption rapidly increases FRAP but the effect appears to be short-lived and is perhaps related to the short half-life of the antioxidant tea phytochemicals in plasma. Moreover, green tea appears to have a greater antioxidant capacity (FRAP) than black tea, and the consumption of black or green tea with or without milk does not appear to effect the rise of the blood's antioxidant capacity. Extracts of food such as green tea extract and grape seed extract also increase postprandial antioxidant status. Although these findings are compelling, a more important outcome than a change in plasma antioxidant capacity is the protection of lipid, protein, and DNA from damage. This is particularly true since some studies show no effect on total antioxidant capacity but do show a change in the degree of protein or lipid oxidation.

Gaining Weight 101

Gaining Weight 101

Find out why long exhausting workouts may do more harm than good. Most of the body-building workout and diet regimens out there are designed for the guys that gain muscle and fat easily. They focus on eating less and working out more in order to cut the excess fat from their bodies while adding needed muscle tone.

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