Lead investigator Dr. Sibu Saha of the University of Kentucky in Lexington and colleagues said the study used animal mice with diet-induced high cholesterol.
A control group was given water to drink, while the experimental group was given watermelon juice.
By week 8 of the study, the animals given watermelon juice had lower body weight than the control group, due to decrease of fat mass, the researchers said.
The mice experienced no decrease in lean mass and plasma cholesterol concentrations were significantly lower in the experimental group, with modestly reduced intermediate and low-density lipoprotein cholesterol concentrations as compared to the control group, Saha said.
A measurement of atherosclerotic lesion areas revealed that the watermelon juice group also experienced statistically significant reductions in atherosclerotic lesions, as compared to the control group.
"Melons have many health benefits," Saha said in a statement. "This pilot study has found three interesting health benefits in mouse model of atherosclerosis. Our ultimate goal is to identify bioactive compounds that would improve human health."