No solid research has shown any food or drink that makes a significant difference in how fast we burn calories.
Grapefruit juice is very nutritious.
Since grapefruit juice can interfere with the body's ability to use some medications, check with your doctor or pharmacist. But drinking large amounts of any juice is usually not a good weight loss strategy, because the calories soon add up and hunger isn't satisfied for very long. A better strategy is boosting solid fruit and vegetable consumption to the recommended five to ten servings a day. These foods are generally low in calories, but their bulk helps satisfy hunger. Copyright 2001 American Institute for Cancer Research.