Prehypertension is characterized by systolic blood pressure readings of 120-139 millimeters of mercury (mm Hg) over diastolic pressure of 80-89 mm Hg. If left unattended, prehypertension can progress to full-blown hypertension, a major risk factor for heart attacks and strokes.
Arturo Figueroa et al found that when six grams of the amino acid L-citrulline from watermelon extract was administered daily for six weeks, there was improved arterial function and consequently lowered aortic blood pressure in all nine subjects
There was a significant treatment effect (change in the value of watermelon minus placebo from baseline to 6 weeks) on brachial Pulse Pressure (about ‐8 mm Hg), and aortic Systolic Blood Pressure (about ‐7 mm Hg), both of which are reliable predictors of cardiovascular risk
Sweet, low calorie, high fiber, nutrient rich watermelon is not only rich in vitamin A, B6, C, fiber, potassium and lycopene, it is also the richest edible natural source of L-citrulline.
Once in the body, the L-citrulline is converted into L-arginine, the amino acid required for the formation of nitric oxide which relaxes blood vessels to regulate vascular tone and maintain healthy blood pressure.
The other good news is that this nitric oxide boosting effect is the same basic effect that Viagra has, to treat erectile dysfunction.
So how much watermelon do we need to obtain 6 grams of L-citrulline?
Rimando AM and Perkins-Veazie PM found that citrulline content ranged from 3.9 to 28.5 mg/g dry weight (dwt). the rind contained more citrulline than flesh on a dry weight basis (up to 24.7 mg/g dwt. Red flesh watermelons had slightly less citrulline than the yellow or orange flesh watermelons. Note that these data are obtained from a dry weight basis; the amount of citrulline obtainable from fresh water melon is 5 to 10% of that from dried fruit.
Now for the caveat: optimistically, 2.10kg of fresh water melon, a whole melon to get enough citrulline to boost the body's arginine level. Running to the bathroom more because of the natural diuretic effect of water melon will be the least of your concern when you read about the toxicity and the liberal use of the insecticide carbofuran in our local orchards.
It is said that carbofuran is active for one whole year (12 months) and is most powerful and effective during the first 90 days.
The watermelons mature and are picked after 55 days, when the carbofuran is still powerful, and a lot of it is inside the watermelons! Read more about this risk in Dr Lim Hin Fui’s blog.
Zestzfulness says: It is quite safe to enjoy the occasional water melon. If you are prehypertensive, wake up and make the necessary lifestyle changes, such as exercising and eating healthier and visiting your health care provider regularly. If you think you need Viagra, talk to your doctor and if you think you're "pre-Viagra", CLICK HERE to see how Zestz can help boost your performance
- Arturo Figueroa, Marcos A. Sanchez-Gonzalez, Penelope M. Perkins-Veazie, Bahram H. Arjmandi. Effects of Watermelon Supplementation on Aortic Blood Pressure and Wave Reflection in Individuals With Prehypertension: A Pilot Study. American Journal of Hypertension, October 2010; FULL TEXT
- Rimando AM, Perkins-Veazie PM. Determination of citrulline in watermelon rind. Journal of Chromatography A. 2005 Jun 17;1078(1-2):196-200.
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