WEST LAFAYETTE, Ind.—Eating watermelon may significantly help boost heart health and reduce weight, according to a new study published in the Journal of Nutritional Biochemistry. The findings suggest the compound citrulline, found naturally in watermelon, plays a key role in heart health.
Researchers from Purdue University and University of Kentucky conducted a study that showed mice fed a diet including watermelon juice had lower weight, cholesterol and arterial plaque than a control group. The research builds upon a study conducted last year at the University of Kentucky that found incorporating watermelon into a diet helped lower their risk of atherosclerosis.
"We were interested in citrulline because previous studies showed that it may lower blood pressure," said Shubin Saha, a Purdue Extension vegetable specialist and study co-author. "We didn't see a lowering of blood pressure, but these other changes are promising."
For the study, the researchers fed two groups of mice diets high in saturated fat and cholesterol. Half the mice received water containing 2% 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 mice that consumed watermelon juice gained about 30% less weight than the control group and had about 50% less low-density lipoprotein (LDL). The experimental group also had about a 50% reduction in 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."
The researchers plan to continue to look at how concentrations of citrulline and lycopene, another compound found in watermelon, affect health. They also will test other varieties to determine whether particular watermelons have more health benefits.