Watermelon could significantly reduce blood pressure in overweight individuals both at rest and while under stress. “The pressure on the aorta and on the heart decreased after consuming watermelon extract,” the small study concludes.
Be sure to pick up a watermelon — or two — at your local grocery store. It could save your life.
A new study by Florida State University Associate Professor Arturo Figueroa, published in the American Journal of Hypertension, found that watermelon could significantly reduce blood pressure in overweight individuals both at rest and while under stress.
“The pressure on the aorta and on the heart decreased after consuming watermelon extract,” Figueroa said.
The study started with a simple concept. More people die of heart attacks in cold weather because the stress of the cold temperatures causes blood pressure to increase and the heart has to work harder to pump blood into the aorta. That often leads to less blood flow to the heart.
Thus, people with obesity and high blood pressure face a higher risk for stroke or heart attack when exposed to the cold either during the winter or in rooms with low temperatures.
So, what might help their hearts?
It turned out that watermelon may be part of the answer.
Figueroa’s 12-week study focused on 13 middle-aged, obese men and women who also suffered from high blood pressure. To simulate cold weather conditions, one hand of the subject was dipped into 39 degree water (or 4 degrees Celsius) while Figueroa’s team took their blood pressure and other vital measurements.
Meanwhile, the group was divided into two. For the first six weeks, one group was given four grams of the amino acid L-citrulline and two grams of L-arginine per day, both from watermelon extract. The other group was given a placebo for 6 weeks.
Then, they switched for the second six weeks.
Participants also had to refrain from taking any medication for blood pressure or making any significant changes in their lifestyle, particularly related to diet and exercise, during the study.
The results showed that consuming watermelon had a positive impact on aortic blood pressure and other vascular parameters.
Notably, study participants showed improvements in blood pressure and cardiac stress while both at rest and while they were exposed to the cold water.
“That means less overload to the heart, so the heart is going to work easily during a stressful situation such as cold exposure,” Figueroa said.
Figueroa has conducted multiple studies on the benefits of watermelon. In the past, he examined how it impacts post-menopausal women’s arterial function and the blood pressure readings of adults with pre-hypertension.
In addition to being published in the American Journal of Hypertension, the study was also published in the US National Library of Medicine National Institutes of Health and was one of the “top new hypertensive articles” in MDLinx.
The above story is based on materials provided by Florida State University. Note: Materials may be edited for content and length.
A. Figueroa, A. Wong, R. Kalfon. Effects of Watermelon Supplementation on Aortic Hemodynamic Responses to the Cold Pressor Test in Obese Hypertensive Adults. American Journal of Hypertension, 2014; DOI: 10.1093/ajh/hpt295
Florida State University. “Chowing down on watermelon could lower blood pressure, study suggests.” ScienceDaily. ScienceDaily, 3 April 2014.
Effects of Watermelon Supplementation on Aortic Hemodynamic Responses to the Cold Pressor Test in Obese Hypertensive Adults
BACKGROUND Cold-induced increases in aortic blood pressure (BP) may cause adverse cardiac events in hypertensives by increasing ventricular afterload. L-citrulline supplementation reduces BP at baseline and during the cold pressor test (CPT), but the effect on wave reflection (augmentation pressure (AP) and index (AIx)) is controversial. Our aim was to assess the effect of L-citrulline–rich watermelon supplementation on aortic hemodynamic responses to CPT in hypertensive adults.
METHODS Brachial systolic BP (bSBP) and aortic systolic BP (aSBP), AP, AIx, AIx adjusted to 75 beats/min (AIx75), reflection time (Tr), first (P1) and second systolic peak (P2; wave reflection magnitude), heart rate (HR), and systolic time index (STI; myocardial oxygen demand) at baseline and during CPT and magnitude of the response from baseline to CPT were evaluated in 13 individuals (10 women; 57±1 year; bSBP 151±5mm Hg). Participants were randomized to a 6-week watermelon or placebo supplementation in a crossover design.
RESULTS Watermelon reduced (P < 0.05) bSBP, aSBP, P1, and P2 at baseline and CPT compared with placebo; thus, increases from baseline to CPT were unaffected. Watermelon did not affect AP, AIx, AIx75, and STI at baseline but decreased (P < 0.05) AP and STI during CPT and the increases in AP (~5mm Hg) and AIx75 (~7.3%) from baseline to CPT.
CONCLUSIONS Watermelon supplementation reduced aortic BP and myocardial oxygen demand during CPT and the magnitude of the cold-induced increase in wave reflection in obese adults with hypertension. Watermelon may provide cardioprotection by attenuating cold-induced aortic hemodynamic responses.