I have a friend who was told not to eat grapefruit as can/would interfere with her prescribed medication, think it is for high b.p.
If it were me, I'd do whatever I could, not to be taking pharma meds, but then, who knows......I love grapefruit, but only eat small amounts of fruits at present, as I am a fast oxidizer type, ie "hunter' GT, and need proteins/fats much more for sustained energy and good brain function, so for me, berries, pear, apple, peach only sometimes, grapefruit - TCM says has cooling energy, I still eat a little in cooler seasons too. I read this fruit good for removing inorganic calcium deposits from joints such as knee joints, so can prevent arthritis down the track perhaps. go grapefruit!!