Watermelons are the perfect summer fruit; magically cool on the hottest of days, sweet (without being overwhelmingly so), and beautifully colored — with a contrasting pink interior with black seeds and green striped rinds, they pretty up the picnic or BBQ table instantly. Now, scientists have found they do more than look and taste great; watermelon has been found to lower blood pressure in a newly released study from Florida State University.
Holistic health experts have long championed the melon for the low number of calories per serving coupled with abundant natural fiber, lycopenes that give the fruit its color, and the high water content. (Water in watermelons is full of electrolytes and nutrients, including vitamins A, B6 and potassium.)
Florida State University researchers Arturo Figueroa and professor Bahram H. Arjmandi administered six grams of L-citrulline/L-arginine (an amino acid taken from watermelon extract) every day for six weeks and found, among their nine male and female subjects, that the extract improved arterial function and lowered blood pressure in the aorta in all the people tested, all of whom were prehypertensive. Hypertension is one of the main precursors to heart attack.
This is the first study of this kind done linking watermelon and blood vessel function.
Lead researcher Figuera told the FSU news website, 'We are the first to document improved aortic hemodynamics in prehypertensive but otherwise healthy middle-aged men and women receiving therapeutic doses of watermelon. These findings suggest that this 'functional food' has a vasodilatory effect, and one that may prevent prehypertension from progressing to full-blown hypertension, a major risk factor for heart attacks and strokes."
About 60 percent of American adults are hypertensive or prehypertensive, and the researchers said that eating watermelon regularly, or taking an extract, could keep heart attacks at bay or keep those who are prehypertensive from becoming hypertensive, or allow them to use less medication.
“Individuals with increased blood pressure and arterial stiffness — especially those who are older and those with chronic diseases such as type 2 diabetes — would benefit from L-citrulline in either the synthetic or natural (watermelon) form,” Figueroa said. “The optimal dose appears to be four to six grams a day."
Fresh watermelon, or watermelon extract, is the best way to get L-citrulline (along with all the other health benefits from the fruit), but it's also available in synthetic form for those who may not like the taste of watermelon. In other studies, the synthetic form of the amino acid was shown to reduce aortic blood pressure associated with cold weather (heart attacks are more common in colder weather, as the body has to work harder to pump blood to the extremities).
An easy way to get watermelon is to make watermelon juice, which is as simple as throwing some cubed watermelon into a blender and pureeing at the highest setting available on your machine. A good 30-45 seconds should do it. Just pour it into a glass (with some ice if you prefer your drinks cold), and voila, you have a tasty, all-natural drink to accompany brunch, or as a great mid-afternoon snack. Be sure to drink it right away, as the water and the fiber from the fruit will separate over time (you can just shake it to mix them again).
To learn more, read the original study in the American Journal of Hypertension.