The findings published in the American Journal of Hypertension state that watermelon can significantly reduce blood pressure in overweight individuals at rest and while under stress.
The study took the concept that more people die of heart attacks in cold weather because the stress of cold temperatures causes blood pressure to increase. The heart must work harder to pump blood into the aorta which often leads to less blood flow to the heart. People with obesity and high blood pressure face a higher risk for stroke or heart attack when exposed to the cold during the winter or in rooms with low temperatures.
The 12-week study consisted of 13 middle-aged obese men and women with high blood pressure that were divided into two groups. Cold weather conditions were simulated by dipping the participants hand into 39 degree water and taking their blood pressure and other vital measurements.
For six weeks one group was given every day four grams of L-citrulline amino acid and two grams of L-arginine both from watermelon extract. Group two was given a placebo and after six weeks the groups switched. The groups also were not allowed to take any blood pressure medication or make any significant lifestyle changes related to diet and exercise during the study.
As it turns out watermelon may be a part of the answer toward helping their hearts.
- Consuming watermelon had a positive impact on aortic blood pressure and other vascular parameters.
- Study participants showed improvements in blood pressure and cardiac stress while at rest and exposed to cold water.
The pressure on the aorta and on the heart decreased after consuming watermelon extract, Figueroa said. That means less overload to the heart so the heart is going to work easily during a stressful situation such as cold exposure.
Watermelon And Post-Exercise Muscle Soreness
In 2013, watermelon juice was found to relieve post-exercise muscle soreness. The study posted in ACS Journal of Agricultural and Food Chemistry attributed watermelons effects to the amino acid L-citrulline as well.
The researchers tested natural watermelon juice, watermelon juice enriched in L-citrulline and a control drink containing no L-citrulline on participants one hour before exercise. The natural juice and the enriched juice relieved muscle soreness. However, L-citrulline in the unpasteurized natural juice seemed to be more bioavailable in a form the body could better use.