Guavas are a super food in many ways. It's juice is an effective remedy to treat dengue fever and is recommended to drink it at least three times in a day for effective results. Guava fruit juice is an astringent that can give you instant relief from toothache and mouth and gum sores. It can improve brain function because it improves circulation in your body. Because it contains high levels of potassium, it helps in regulating blood pressure. It has been reported that this mineral can help in reversing the effects of excessive sodium in the body. Guava Juice is a best way to treat constipation and diarrhea as it is filled with fiber. Consume guava juice before the breakfast for best results. Guava juice can be a useful remedy to decrease the cancer cell development.