When Good Foods Are Bad for You

Grapefruit

Even good foods can cause havoc in your life. Here are a few to keep your eye on.

Grapefruit

Prescription drug interaction and potential kidney failure

While grapefruit is an excellent source of vitamin C and contains fiber, potassium, and lycopene for cancer prevention, it could be off-limits for those on some prescription medications. "It can alter the effects of the drug, causing serious side effects. The biggest concerns are with cholesterol-lowering medications. The grapefruit may prevent the liver from breaking down the drug, causing toxic levels to build up that could cause kidney failure," says Lona Sandon, MEd, RD, a professor of nutrition at the University of Texas Southwestern Medical Center at Dallas.

"One glass of grapefruit juice or one grapefruit is enough to interfere with medications. I am not sure at what level kidney failure might occur, but it's probably not a good idea to push it. It likely depends on a person's body weight. No level of grapefruit intake is considered acceptable with these medications," says Sandon.