A study in California evaluated the antioxidant capacity of blood immediately after consuming pecans. In addition to measuring the antioxidant capacity, researchers also measured the levels of various antioxidants such as tocopherols and catechins in order to find out whether the antioxidants that are present in pecans are easily absorbed in the intestine. The results proved that consuming pecans enhances the antioxidant capacity of blood and reduces the oxidation of LDL, a protein that is the major carrier of cholesterol in the blood.
The pecan originates from the Central Southern part of the United States and is readily available. Many earlier studies have shown that pecans are a rich source of antioxidants such as flavonoids and catechins. Antioxidants protect us against various toxins and reduce the risk of heart disease. In the present study, researchers wanted to determine whether the antioxidants present in pecans are absorbed by our intestines, and if so to what extent they increase the antioxidant capacity of blood. This study compared the levels of antioxidants in the blood of people who consumed a meal free of pecans with those who consumed a pecan-rich meal.
* The study included 16 healthy participants of which six were men and 10 were women.
* Some of the participants were asked to consume a test meal consisting of 90 gm of pecans mixed with water. The remaining participants were asked to consume a control meal that consisted of the same calorie content as that of the test meal, but without pecans.
* Blood samples were collected from participants before the start of the experiment, and at one, two, three, five, eight and 24 hours after the consumption of the meals. The antioxidant capacity of blood was measured. In addition blood levels of flavonoids, tocopherols and oxidized LDL were measured.
* There was no difference in the baseline levels of antioxidants in all participants.
* Blood antioxidant capacity after consuming the pecan-rich meal was 9.2 units, but it was only 8.4 units in the case of the control meal. A significant increase was noted in a certain kind of antioxidant called gamma-tocopherols at five and eight hours after the pecan-rich meals.
* After the consumption of the whole pecan meal, oxidized LDL (carrier of cholesterol in the blood) decreased 29.6, 33.3 and 26.3 percent from the baseline at two, three and eight hours, respectively.
On comparing the results of consumption of whole pecans with blended ones, very few differences were found between the two. This experiment is the first to investigate the effects of consuming pecans on the antioxidant capacity of blood. However, the study failed to establish exactly how nuts in the diet exert a protective effect. Although catechins and gamma-tocopherols increased along with a concomitant increase in blood antioxidant capacity, the precise mechanism underlying their improved bioavailability needs further research.
It was observed in earlier epidemiological studies that the consumption of pecans is associated with low incidence of various heart problems. It was also observed that they significantly reduced lipid levels in blood. Though many antioxidants have been identified in pecans, this is the first study that evaluated the bioavailability of antioxidants present in pecans. The study also highlights the nutritive value of pecans in providing antioxidants, thus emphasizing the need to create an awareness regarding the positive health properties of pecans. Adding more pecans to the diet is likely to help reduce the risk of cardiac disease and some degenerative diseases, as oxidant damage to cells plays a part in the onset of these diseases.
For More Information:
Pecans Increase Antioxidant Capacity of Blood and Decrease LDL Oxidation in Humans
Publication Journal: The Journal of Nutrition, November 2010
By Chatrapa Hudthagosol; Ella Hasso Haddad; Loma Linda University, Loma Linda, California