In a recent study conducted by the Texas A&M's Fruit and Vegetable Improvement Center, it was found that watermelons contain an ingredient called citrulline that can stimulate production of a compound, arginine, an amino acid that helps relax the body's blood vessels. The same effect is produced when a man takes viagra.

"Citrulline reacts with the body's enzymes when taken in large quantities and changes into arginine, which boosts nitric oxide. Nitric oxide then relaxes blood vessels, which is similar to the effect produced by viagra, to treat erectile dysfunction," said Dr. Bhimu Patil, a researcher and director of Texas A&M's Fruit and Vegetable Improvement Center.

Nitric oxide can also prove helpful in the treatment of angina, high blood pressure and cardiovascular problems.

"But people taking viagra should not except same results from watermelons," Todd Wehner of North Carolina State University said.

But Penelope Perkins, a USDA researcher in Lane, Oklahoma, points out some side effects which might result from the excessive intake of watermelons. According to her, in order to get enough citrulline to boost body's arginie level, one needs to take about six cups of watermelon, which can reslut in Diarrhea, because watermelon is a deuratic. Watermelon is rich in sugar, so they can also increase the sugar levels in the bloodstream.

However Dr. Bhimu Patil says that they'll be conducting future studies on reducing the sugar content and increasing the citrulline levels in watermelon. Dr. Patil also restated that the relation between watermelon and developing erection, could only be proved after a clinial trial.