Top Foods for Male PerformanceWhen you sink your teeth into a slice of sweet, juicy watermelon, did you know you also could be enjoying a natural treatment for erectile dysfunction? Watermelon is a great source not only of beta-carotene and lycopene – two important phytonutrients for the heart and for sexual function—but also citrulline. Citrulline is important for several reasons. One, it can relax the blood vessels, which in turn improves blood flow. Two, when you eat citrulline-rich watermelon, the body transforms citrulline intoarginine. The amino acid arginine boosts the body’s levels of nitric oxide, which in turn relaxes the blood vessels in the penis and promotes an erection, which is the same basic effect Viagra has on the body. Although it might be a stretch to say that watermelon could be an erectile dysfunction treatment, it certainly won’t hurt to try it.