Pomegranate, known as the royal fruit because of the 'crown' on top, is also the shining light for how to capitalise on consumers' growing interest in exotic fruits and ensure they offer benefits and not empty hype, say experts.
"Pomegranate is an ideal platform to investigate exotic fruits' impact on human health and disease," said Navindra Seeram from the University of California, Los Angeles (UCLA) at the SupplySide West International Trade Show and Conference. Increased consumer interest in exotic fruits has seen the likes of acai, goji, noni, mangosteen and pomegranate move in to the mainstream. Indeed, in Europe the increased popularity of exotic fruit contributed significantly to a growth rate of 26 per cent for the European organic food industry between 2001 and 2004, according to market analyst Datamonitor, with the US market following suit. Seeram told attendees in Las Vegas however that consumers are frequently confused by a variety of health claims often based on in vitro experiments, which may not necessarily be transferable into in vivo effects.
By following the example of building the science behind pomegranate, the claims behind other exotic fruits could be substantiated. "The take-home message," said Seeram, "is to take the fruit/ product and plan careful, basic studies combined with clinical studies." Pomegranate, a rich source of antioxidants , has been linked to improved heart health, but a growing body of science indicates the fruit protect against prostate cancer and slowing cartilage loss in arthritis. It is these antioxidants, and particularly compounds like punicalagin, which accounts for about half of the fruit's antioxidant ability, that are reportedly behind the proposed health benefits.
Seeram presented old and new data supporting the potential role of pomegranate juice and extracts to reduce the risk of prostate cancer, a disease that is diagnosed in over half a million men worldwide every year. Over 200,000 deaths occur from the disease. The transition from a healthy prostate to the development of cancer as a result of chronic inflammation can take between 10 and 15 years, he said, making it "ideal for nutritional prevention." Recapping results from the clinical trial published last year in Clinical Cancer Research, Seeram stated that a daily dose of eight ounces of pomegranate juice was associated with an increase in the doubling time of prostate-specific antigen (PSA) from 15 to 54 months, indicating improved prostate health. PSA is a marker commonly used to screen for prostate cancer and for tracking the disease after its diagnosis.
Seeram said that the trial is ongoing with new, unpublished results showing the daily glass of pomegranate juice could increase PSA doubling time to 58 months. He also revealed that pomegranate extracts could produce similar results to the juice, with more unpublished results indicating that equivalent levels of plasma and urinary metabolites were measured as a result of either juice or extract administration, but the maximum effect was delayed from one to two/three hours in subjects receiving the extract. NutraIngredients.com has not seen this data.
Taken in its entirety, Seeram said that the studies allow scientists to look at the "full picture", and called for researchers to follow this example for other exotic fruits.