Scientists from the University Miguel Hernandez in Alicante report that exercise can increase markers of oxidative stress like malondialdehyde (MDA), a reactive carbonyl compound. Consuming 200 ml per day of pomegranate juice, however, prevented these increases or actually decreased MDA levels.
“The volunteers of this study were chosen from different sport clubs in Southeastern Spain,” explained the researchers in Nutrition. “Nevertheless, we can state that the results could be applicable to adult males that frequently practice endurance-based sports, but further investigation of the use of pomegranate juice in endurance sport athletes needs to be replicated in larger clinical trials.”
The study adds to a long list of potential health benefits for the fruit. Pomegranate, a rich source of antioxidants, has been linked to improved heart health, prostate health, and joint health. It is these antioxidants, and particularly ellagitannin compounds like punicalagins and punicalins, which accounts for about half of the fruit's antioxidant ability, that are reportedly behind the proposed health benefits.
The study used the commercial product provided by Vitalgrana SL and the company funded the study.
The researchers noted that the manufacturing process for the juice may play an important role in any potential outcomes: “The juice used in this study contains a mixture of inner and outer peels as well as from the seed,” they said. “Therefore, the antioxidant capacity of the product tested in this study could be considered higher than that from other juices that do not use these sub-products.”
Twenty-two athletes were recruited to participate in the randomized, double-blind, multicenter trial. The athletes were randomly assigned to consume either the pomegranate juice or no juice (control group) for 21 days.
Results showed that levels of carbonyls and MDA increased in the control group, but baseline levels were maintained in the pomegranate group.
The researchers also reported a non-significant decrease in levels of C-reactive protein, a marker of inflammation, in the pomegranate group.
“Consumption of pomegranate juice during 22 days is capable of modulating fat and protein damage, as the changes in MDA and carbonyl levels indicated,” they wrote. “The high presence of antioxidant polyphenols also supports this recommendation.
“Finally, the evaluation of pomegranate juice consumption regarding training intensity, as well as the study of circulating parameters such as blood lactate, K+ and AST, needs to be analyzed in further studies.”
Published online ahead of print, doi: 10.1016/j.nut.2015.11.002
“Effects of Pomegranate Juice in Circulating Parameters, Cytokines and Oxidative Stress Markers in Endurance-Based Athletes: A Randomised Controlled Trial”
Authors: E. Fuster-Munoz, et al.