My favorite summer fruit since I was a child...it has many vitamins and minerals that are great for your heart. Watermelon contains citruline, an amino acid that may increase nitric oxide (helps blood vessels expand) levels, which help lower blood pressure. It also contains vitamins A, B6, C, magnesium and potassium. I've read that it should be eaten by itself since it is very filling. Also, I've read that if you want to pick a sweet one, pick one that has a creamy yellow spot on its resting side. That's how you'll know it's ripe. Being from Texas, it's the best thing to eat when it's really hot outside!