Scientists Agree That Grapefruit Isn’t Always Great Fruit

Written by | Food, Wellness

Pink Grapefruits

Photo courtesy istock / ValentynVolkov

Grapefruit is a snack with a variety of health benefits — but if you take certain medications, you may have to take it off the menu.

Grapefruit can be a delicious delicacy. Some like it with a little sweetener; some prefer a few sprinkles of salt; still others squeeze them for juice or toss them into a salad.

The tart citrus fruit offers offers assorted health benefits. A study by the Scripps Clinic found that it’s been associated with increased weight loss when dieting and it may help prevent insulin resistance (a cause of Type 2 Diabetes). The American Heart Association reports that grapefruit can lower the risk of stroke in some by as much as 20 percent. Its potassium content has also been credited with protecting bones and preventing kidney stones. (Potassium has also been linked to lowered blood pressure because of its ability to help open blood vessels.)

There’s more: the antioxidants and Vitamin C in grapefruit have been found to lower the risk of developing certain cancers and asthma. Enjoying grapefruit is also a natural way to stay hydrated since it’s composed of ninety percent water, and its high fiber content can assist regulating the digestive system.

However, many remain unaware of the dangerous ways grapefruit interacts with certain types of medications. How? Well, for any drug to work correctly, it needs to be properly absorbed. The heavy lifting in this process is commonly done by an enzyme called CYP3A4. Unfortunately, chemical compounds in grapefruit can block that enzyme from accomplishing its mission.

This can have two effects on medications: In one instance, blocking the enzyme prevents proper absorption — causing there to be a surplus in the system. That can be perilous, according to FDA deputy director Shiew Mei Huang. “When there is a higher concentration of a drug, you tend to have more adverse events,” she explains. In another case, grapefruit might also block transport enzymes from carrying the drug to its intended destination, causing patients to receive an insufficient dosage. The results can range from mildly irritating to life-threatening.

Drugs that interact poorly with grapefruit include some designed to lower cholesterol or to lower blood pressure. Certain anti-anxiety and antiarrhythmia drugs may also be affected — in addition to some antihistamines and organ transplant rejection drugs. If you take medication designed to address any of these conditions, definitely consult the proper medical professionals before digging in.

Last modified: June 21, 2017