Watermelon, even out of season, can be used to create nutraceuticals -- foods or food components that offer health benefits. Shubin Saha, Pudue University
Sweet and juicy watermelon could be one of nature's best medicines, since scientists have just found out that it could keep cardiologists at bay.
A study, published in the Journal of Nutritional Biochemistry, suggests that citrulline, a compound found in watermelon, helps consumers to reduce weight, diminish arterial plaque, and lower their levels of bad LDL cholesterol.
"We were interested in citrulline because previous studies showed that it may lower blood pressure," Shubin Saha, a Purdue Extension vegetable specialist and study co-author, was quoted as saying in a press release. "We didn't see a lowering of blood pressure, but these other changes are promising."
Saha and his colleagues fed two groups of mice diets high in saturated fat and cholesterol. Half the mice received water containing 2 percent watermelon juice, while the others received the same amount of water supplemented with a solution that matched the carbohydrate content of the watermelon juice.
The watermelon juice drinkers gained 30 percent less weight than the control group and had around 50 percent less LDL cholesterol. They also had a 50 percent reduction of plaque in their arteries, as well as elevated levels of citrulline.
"We know that watermelon is good for health because it contains citrulline," said Sibu Saha, a professor of surgery at the University of Kentucky. "We don't know yet at what molecular level it's working, and that's the next step."
Saha said that about 20 percent of each year's watermelon crop is wasted, either because the fruit is visibly unappealing to consumers or because some growers find it too expensive to pay for harvesting as prices drop during the height of watermelon season. (While we're past the summer season peak, U.S.-grown watermelons should still be available to most American consumers through November.)
Watermelons are an important homegrown crop, with the U.S. leading all exports. Eighty-eight percent go to Canada, with the remainder sent to Japan, Mexico, Russia, Bermuda and France.
If the otherwise-wasted melons could go toward nutraceuticals -- foods or food components that offer health benefits -- that'd obviously be a win-win for everybody. I'd prefer to eat the fresh and ripe organic fruit, though. It's been a fave for ages, with watermelon mentioned in the Bible and seen in ancient Egyptian images. Watermelon seeds were even found in King Tutankhamun's tomb.
"We could use the wasted melons that can't go to market for extracting beneficial compounds," Shubin Saha said. "Growers are putting energy into these crops, so if we can do something to help them market their additional product, that would be a benefit to the industry and consumers."
Scientists are also investigating lycopene, another component in watermelon that shows promise in benefiting human health.