Watermelon skin can be eaten; however, inorganic melons may have pesticides on them. Watermelons should be washed before being cut to avoid spreading the pesticides to the flesh. The seeds are also edible and are enjoyed as snacks in many parts of the world.
Watermelon skin contains many nutrients including L-citruline. L-citruline helps improve blood circulation by dilating the blood vessels. Ripe watermelons are the most nutrient dense and can be identified by having a yellow underbelly.
The flesh of watermelons are high in vitamin C, copper, pantothenic acid and biotin. There are 46 calories in one cup of diced watermelon.