Wednesday, January 23, 2013

POM Wonderful?

Species name: Punica granatum

Common name: pomegranate

Location: UWO Greenhouse

The pomegranate is native to Iran and Iraq, and has been used as a source of food and medicine by humans for centuries (arguably millennia). It is now widely grown as a tree crop around the world, and is also often now planted as an ornamental species both for its flowers (which are spectacular), the fruits (yum), and the bark (twisted and knotty; it's also quite spectacular-looking). There are even cultivars of pomegranate that were created in greenhouses specifically for their flowers, and the fruits don't even form. Seems like a waste of a pomegranate plant to me!

Pomegranates aren't just known for their edible seeds. Actually, it's not even the seeds that you consume! Like in some gymnosperms or cone-bearing plants, the seeds have a fleshy covering around them called an aril (you can read more about gymnosperms with an aril HERE and HERE). This aril is the red, juicy bit around the tough white seed. It's not that the seed is bad for you (unlike in the examples above, where the seed is deadly), it's just that the plant wants small animals to consume the aril with the seed inside, then poop the seed out intact. This gives the seed a nutritious medium to grow in, and it ensures that the seeds are dispersed away from the plant (unless the plant has the misfortune of having the animal leave the plant, then return to it and deposit the "organic matter").

For centuries, the pomegranate has been used as a medicinal plant, even before we started touting its "anti-oxidant" properties. Indian people are the most well-known for their use of pomegranates in Ayurvetic medicine going back at least a millennium (likely significantly longer than that). The rind, or the outside of the fruit (the "skin" that most people throw out) was used to make a type of tea that would be consumed to stop intestinal discomfort like diarrhea and problems related to dysentery. The juice and seeds of the plant would be consumed in a tonic to soothe sore throat and treat heart palpitations, as well as a treatment for heart attack. The seeds themselves would be consumed as an agent inducing abortion and as a contraceptive. The juice of the arils also has a reported use when applied topically on the skin to clear blemishes and help fade scars and rashes. There are a boatload of health benefits that herbal medicine practitioners in North America and Europe will tell you that the pomegranate has. First, it is claimed that it will reduce cholesterol and unblock arteries and veins in your heart (and reduce other risk factors for heart disease). Next, it's claimed that it will prevent the formation of cancer tumours due to its anti-oxidant properties, and will halt or reverse the growth of tumours that are already present. Lastly, it's claimed that pomegranate juice is an effective anti-bacterial chemical and will prevent infection in wound sites as well as preventing bacterial growth in your mouth when you consume it.

So what claims have been substantiated with actual evidence? None. There are suggestions, correlations, that pomegranate juice prevents (to some degree) plaque formation on your teeth by inhibiting bacterial growth. But remember, this is the bacteria in your mouth, not the bacteria on your skin. This doesn't mean it will prevent infection on your skinned knees. There is NO evidence that the anti-oxidants present in pomegranate juice will have any effect on your circulatory (or other) system. None. Don't get fooled by claims that there is evidence it does anything, because it doesn't. In fact, the leading brand of pomegranate juice, POM Wonderful, was sued for making illegal health claims on their product's label. The claims have since been removed. That being said, there are currently 32 enormous scientific trials underway in the United States testing the reported effects of pomegranates on different conditions. You can find all of the clinical trials on the National Institutes of Health website (NIH Clinical Trials), and what stage of the trial has been completed. None of them have published data (but it will be coming).