By day three, watermelon’s water and fiber content will support better digestion, prevent constipation, and help maintain a healthy gut. By the fifth day, if you need to unwind after a busy day, watermelon can help with that too. It contains magnesium, a key mineral that soothes nerves, relieves headaches, and even improves sleep quality. Eating watermelon daily may also reduce the risk of cardiovascular disease and certain cancers, thanks to its nutrient rich profile and antioxidants