Grapefruits are a good food to include in a sensible weight-loss diet. They are low in calories and their high-fibre content keeps you full longer. Grapefruit is also known to ease pain associated with inflammatory disorders. This may be because certain plant chemicals in grapefruit block prostaglandins, some of which can cause inflammation. Research shows that people with rheumatoid arthritis, lupus, and other inflammatory disorders find that eating grapefruit daily seems to alleviate their symptoms.