Table 3.

Studies investigating the impact of watermelon extract on vascular outcomes.

Author	Sample Size (N)	Intervention	Vascular Outcome Measures
	Sex (% Female)	Dose
	Age	Duration
Study Design	Health Status
Massa et al., 2016 (46) Randomized, double-blind, placebo-controlled, parallel study	Intervention N: 20 % Female: 50 Age: 48.7 ± 1.9 y Health Status: prehypertensive and hypertensive Placebo N: 20 % Female: 45 Age: 47.4 ± 1.2 y Health Status: prehypertensive and hypertensive	Intervention: watermelon extract Dose: 4g L-citrulline +2 g L-arginine/d Duration: six weeks	BP Sympathovagal balance measured as autonomic nervous activity
Figueroa et al., 2011 (47) Randomized, double-blind, placebo-controlled, crossover study	N:9 % Female: 55 Age: 54 ± 3 y Health Status: prehypertensive	Intervention: watermelon extract Dose: 2.7 g L-citrulline +1.3 g L-arginine/d Duration: six weeks with four weeks washout between intervention arms	BP PWV PWA measures HR
Figueroa et al., 2012 (49) Randomized, placebo-controlled, crossover study	N: 14 % Female: 78 Age: 58 ± 1 y Health Status: prehypertensive as well as stage 1 HTN. Women were post-menopausal.	Intervention: watermelon extract Dose: 4g L-citrulline +2 g L-arginine/d Duration: six weeks with two weeks washout between intervention arms	BP PWA measures HR Ankle-brachial index
Figueroa et al., 2013 (50) Randomized, placebo-controlled, crossover study	N: 12 % Female: 100 Duration: six weeks with two weeks washout between intervention arms	Intervention: watermelon extract Dose: 4 a L-citrulline +2 a L-arainine/d Age: mean 57y standard error 1y Health Status: obese, postmenopausal women with stage 1 HTN	BP PWV PWA measures HR
Figueroa et al., 2014 (51) Randomized, double-blind, placebo-controlled crossover study	N: 13 % Female: 76 Age: 57.4 ± 1.4 y Health Status: hypertensive, obese, sedentary.	Intervention: watermelon extract Dose: 4q L-citrulline +2 q L-arqinine/d Duration: six weeks with two weeks washout between intervention arms	BP PWA measures Systolic time index

BP, Blood pressure; PWV, pulse wave velocity; PWA, pulse wave analysis; HR, heart rate; HTN, hypertension.