Heart Health Benefits of Pomegranates May Vary Due to Polyphenol Metabolism
Pomegranates are often lauded for their ability to provide much-needed nutrients for heart health. A recent study suggests that heart-health benefits of pomegranates may be dependent on an individual’s ability to metabolize the fruit.
Participants in the study included 49 healthy, overweight or obese people. The researchers placed them into three categories according to the types of urolithin metabolytes they produced: urolithin A (UM-A), urolithin B (UM-B), and non-producers. Urolithin is a microflora that is produced by bacteria in the intestine when dietary ellagic acid derivatives are metabolized.
The study consisted of two 3-week phases, with a 3-week washout period between each phase. During one phase, the participants consumed a low-dose pomegranate extract of 160 mg per day or a placebo. During the other phase, they consumed a high-dose extract of 640 mg per day or a placebo.
The UM-B group showed the highest cardiovascular risk at baseline. However, after the high-dose pomegranate extract supplementation, only the UM-B group showed significant improvements in blood lipid levels. Specifically, total cholesterol decreased by 15.5%, LDL cholesterol levels by 14.9%, small LDL cholesterol levels by 47%, and oxidized LDL cholesterol by 24%.
The researchers hypothesized that people who excrete UM-B are uniquely able to metabolize pomegranate in a way that leads to improved cardiovascular health. This would explain why previous studies have shown varying degrees of success.
Researchers from Campus de Espinardo in Spain, TÜB?TAK Marmara Research Center in Turkey, Karadeniz Technical University in Turkey, and Catholic University of San Antonio in Spain conducted the study. It was published online ahead of print on November 23, 2016, in Molecular Nutrition and Food Research.
Pomegranates are packed with protective vitamins, and ongoing research is investigating their ability to improve heart health, reduce cholesterol, reduce joint pain and possibly reduce the risk of prostate cancer.