view current print edition




New drug interaction-free hybrid could help grapefruit regain market share

by Chip Carter | December 09, 2011
University of Florida researchers recently unveiled a new grapefruit-Pummelo hybrid that does not interfere with prescription drugs. These samples were on display at a recent tasting at UF’s Lake Alfred Research Center. (Photo by Chip Carter)

Grapefruit consumption in the United States has declined steadily over the last decade, influenced in large part by the discovery that the fruit or its juice can interact negatively with some prescription drugs. Researchers at the University of Florida recently announced that a cure for that problem will be available in the not-too-distant future in the form of a new grapefruit-Pummelo hybrid.

“We have the possibility to develop new products that are going to be very similar to grapefruit, and we won’t have these issues. And they can be used as a fresh fruit, or people can make juice from them, and all these folks who are on the medicines won’t have to worry about them,” said Fred Gmitter, a UF citrus researcher at the university’s Citrus Research and Education Center in Lake Alfred, FL. Dr. Gmitter was named the Florida Fruit and Vegetable Association’s Researcher of the Year earlier in 2011 for unrelated scientific efforts.

Dr. Gmitter said that the new fruit likely will not be commercially available within the next five years, but it is on the way. People who have tasted the new product — including a The Produce News editor — have said it has the same appearance and flavor profile as its drug-impacting cousins.

For Florida grapefruit growers, the new fruit cannot come to market quick enough, though they also say educational efforts aimed at correcting misunderstandings about grapefruit and drug interactions have made headway over the past couple of years. Many patients do not understand that they can still include grapefruit in their diets, just not at the same time interval they take their prescriptions.

Dr. Fred Gmitter is part of a team that developed a grapefruit-Pummelo hybrid that does not interact with prescription drugs. (Photo by Chip Carter)

“It’s always a positive when somebody comes out with a variety that’s very unique within that process,” said David Mixon, chief marketing officer for Seald Sweet International in Vero Beach, FL. “At the same time, there’s been good work done on the misinformation and concerns about grapefruit. Will it be a real positive deal to state that there is no negative reaction with the Pummelo variety? Yes, that’s always a positive, but the reality of it is consumers overreacted to the statements that were being used with grapefruit consumption. What damage is done stays done. It’s going to be a long battle, but will [the new fruit] be a quick resolve to some of the battle? Absolutely.”

Researchers first noted what is now commonly called the grapefruit effect in 1989 while studying the effect of alcohol consumption on some drugs. They attempted to disguise the alcohol by mixing it with grapefruit juice and noticed that that the efficacy of some drugs was either increased or decreased substantially more than should have been the case with alcohol alone.

Furanocoumarin, a naturally occurring chemical found in some fruits and vegetables — and in high concentration in grapefruit, particularly the white variety, was identified as the culprit, impacting how much of the drug is absorbed in the bloodstream. Furanocoumarin impacts individual drugs and in some cases — like cholesterol-lowering medications — entire categories.

The development of the new variety, which has yet to be named, started when Florida Department of Citrus research scientist Paul Cancalon, also based at Lake Alfred, asked Dr. Gmitter for samples of Florida-grown grapefruit to compare to grapefruit grown in other places around the world. Dr. Cancalon noticed that the Florida-grown grapefruit demonstrated lower furanocoumarin content than grapefruit grown in other places, prompting a research team to begin checking more grapefruit and Pummelo varieties for furanocoumarin levels. Eventually, several hybrids were found to have almost no furanocoumarin; a seedless variety emerged as the likely future consumer favorite.

Lisa House, a UF professor in food and resource economics who studies consumer preferences, led two focus groups on the new hybrid in Atlanta in early 2011. One group was made up of grapefruit consumers and the other of non-consumers. While the sample size was small, both consumer groups said that the idea of a grapefruit hybrid that did not interfere with prescription drugs was appealing, and they found it to be even more so after taste testing the hybrid. “Both groups saw it as a fruit to add to their diet, not just something to replace grapefruit,” Dr. House said.