Hybrid Grapefruit Busts Drug Interactions

Common grapefruits have a compound that can negatively interact with some medications. A new hybrid grapefruit solves the problem. Katherine Harmon reports

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Grapefruits are off-limits for people on certain medications. The tangy fruits contain compounds called furanocoumarins, which can dangerously increase the effective dosage of some blood pressure and heart medications.

But scientists at the University of Florida have bred a new type of grapefruit that should enable people on meds to enjoy the fruit without the drug interaction.

"There are certain relatives of grapefruit that we call pummelo, some of which are very, very low or have no furanocoumarins in them at all. And we've crossed these with ordinary grapefruit." Fred Gmitter, a citrus geneticist at the University of Florida.

These new hybrid grapefruits have even less of the compounds than do other foods that don't get special warnings. "Doctors don't generally tell their patients not to drink lemonade or not to eat celery. So these should be as safe or safer than lemons or celery."

The findings are described in the Journal of the American Society for Horticultural Science. [Chunxian Chen et al., "Characterization of furanocoumarin profile and inheritance toward selection of low furanocoumarin seedless grapefruit cultivars"]

The new fruits are also seedless. Which should make them an easy switch for consumers to swallow.

—Katherine Harmon

[The above text is a transcript of this podcast.]

Gmitter audio from University of Florida News

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