According to Healthline, watermelon rinds offer more than just fiber. Citrulline is an amino acid found in watermelon rinds that has many benefits. Citrulline can boost your libido, and may even improve your athletic performance by providing more oxygen to the muscle cells. Hypertension sufferers may experience a drop in blood pressure due to this amino acid. This is because the body converts citrulline into another amino acid called L-arginine and a chemical called nitric oxide (via Mind Body Green). This dilates your blood vessels and increases blood flow to your heart and muscles.
Watermelon rind can be prepared in many ways to make it more appealing. Pickling the rind is popular in the Southern United States (via Watermelon.org). The rind can be juiced, or you can cut it into small pieces and fry it as a vegetable. Watermelon rinds can be added to smoothies and are a great way to add nutrients and fiber to your morning beverage. You can save the watermelon skin, whether you juice it or cook it.