点击显示 收起
1 Merck Research Laboratory Blue Bell, PA
2 Nutrition Department Pennsylvania State University University Park, PA 16802 E-mail: pmk3{at}psu.edu
Dear Sir:
Klevay raises a very good question about whether or not copper could have contributed to the results of the lipid oxidation potential in the Cocoa and Dark Chocolate Study reported by researchers at Pennsylvania State University (1). Using nutrient database values, we calculated the copper content of the diets and report the following.
The base diet (averaging the 6 menus), at 2500 kcal/d, provided 0.844 mg Cu/d. (Note that not all foods in the menus have reported copper content; therefore, the total for the base diet and the experimental diet could be higher but would increase by the same amount.) The recommended dietary allowance for copper is 0.9 mg/d; therefore, the diets essentially provided the recommended dietary allowance for this micronutrient (94%). The addition of the dark chocolate (16 g/d) contributed an additional 0.128 mg Cu/d, and the cocoa powder (22 g/d) contributed, depending on the nutrient database used for values, between 0.17 and 0.83 mg Cu/d to the diets.
Therefore, the total copper content of the cocoa–dark chocolate diets was 1.14 mg Cu/d and could have been as much as 1.80 mg Cu/d. The difference between the control diet and the experimental diet was 0.298 and perhaps as much as 0.961 mg Cu/d.
Of note is that the base diet was adequate in copper. Whether the addition of the copper from the cocoa and dark chocolate was significant and whether it contributed to the effects on LDL oxidation would need to be tested. However, it is certainly possible that the copper contributed in some way to the overall antioxidant potential of the diets and the subsequent serum antioxidant capacity.
REFERENCE