The key pomegranate chemicals, called ellagitannins, are also found in foods including strawberries, raspberries, and muscadine grapes, note Navindra Seeram, Ph.D., and colleagues.
Their theory is that when someone drinks pomegranate juice, the juice releases ellagitannins, which get digested into chemicals called urolithins, which may fight prostate cancer.
Seeram's team tested that notion in their lab.
The scientists bought pomegranates and made their own pomegranate extract from pomegranate skin. They closely measured the ellagitannins in their pomegranate juice.
Next, the researchers tested pomegranate juice against human prostate cancer cells grafted into male mice.
The scientists fed the pomegranate juice to some of the mice. They injected the pomegranate juice into other mice's abdomens.
For comparison, the researchers fed or injected other mice with a placebo solution containing no pomegranate juice.
The prostate tumors grew more slowly in the mice that got the pomegranate juice orally or by injection, compared with mice that got the placebo.
Finally, the mice got urolithins orally or by abdominal injection. Those pomegranate-derived chemicals gathered in the mice's prostate, colon, and
intestinal tissues more than in other organs.
Add it all up, and it looks like pomegranate ellagitannins may slow (but not totally destroy) prostate cancer in mice.
More studies are needed to see if pomegranate juice works the same way in people, Seeram and colleagues write in the Journal of Agricultural and Food Chemistry.
By Miranda Hitti
Reviewed by Louise Chang
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