Watermelons are slowly revealing their different benefits. If you thought watermelon is just a fruit that refreshes parched throats, here’s a bit of useful information: the ingredients in the fruit cause Viagra-like effects to the body’s blood vessels and may also help increase libido.

The finding results from a study led by an Indian researcher in the US.

"The more we study watermelons, the more we realize just how amazing a fruit it is in providing natural enhancers to the human body," said Dr. Bhimu Patil, director of Texas A and M’s Fruit and Vegetable Improvement Center in College Station.

"We’ve always known that watermelon is good for you, but the list of its very important healthy benefits grows longer with each study," he added.

Beneficial ingredients in watermelon and other fruits and vegetables are known as phyto-nutrients, naturally occurring compounds that are bioactive, or able to react with the human body to trigger healthy reactions, Patil said.

In watermelons, these include lycopene, beta carotene and the rising star among its phyto-nutrients - citrulline - whose beneficial functions are now being unraveled. Among them is the ability to relax blood vessels, much like Viagra does.

Scientists know that when watermelon is consumed, citrulline is converted to arginine through certain enzymes. Arginine is an amino acid that works wonders on the heart and circulation system and maintains a good immune system, Patil said.