Summer-sweet watermelon is known to be high in fiber and nutrients and low in calories. Now, evidence from a pilot study led by food scientists at Florida State University suggests that eating watermelon might also help dispel pre-hypertension, a precursor to cardiovascular disease.

“Even better, it may prevent the progression from pre-hypertension to hypertension in the first place,” says lead researcher Arturo Figueroa, an assistant professor at the university. A University of Illinois study estimates that as many as 60 percent of U.S. adults have elevated tension levels.

Why might this large-size fruit pose such a benefit? “Watermelon is the richest edible natural source of L-citrulline, which is closely related to L-arginine, the amino acid required for the formation of [the body’s own natural] nitric oxide, essential to the regulation of vascular tone and healthy blood pressure,” says Figueroa. Once in the body, the L-citrulline naturally converts into L-arginine.

The scientists caution that consuming L-arginine as a dietary supplement isn’t a good option, because it can cause nausea and gastrointestinal discomfort; watermelon, on the other hand, provides a safe delivery system. It also has been shown to help reduce serum glucose levels. All of this makes watermelon a “functional food” because it offers health-promoting or disease-preventing properties beyond its delicious taste.