Statins are the most commonly used medications in the U.S. and are used by millions of people to reduce cardio-vascular disease, heart attacks and stroke. For patients who take the three most commonly prescribed, Simvastatin, Lovastatin and Atorvastatin, the current medical advice is to avoid grapefruit juice while talking these medications. Grapefruits and grapefruit juice increase the concentration of these drugs in the body. But a new study published in The American Journal of Medicine says we have it all wrong! Patients who like grapefruits should go ahead and enjoy them with their statins. Here's what the researchers say:
Fresh grapefruit juice contains bergamottin which has an effect on an intestinal enzyme (CYP3A4 for you chemists) that prevents the breakdown of certain statins. The consequence is that the blood level of these three statins are increased when taken with grapefruit juice. We've known about this interaction since is was discovered by accident in 1989 when researchers were studying another drug that is affected by this enzyme. Since that time, patients have been advised to avoid grapefruit juice. But since we know that standard doses of these medications reduce LDL (bad) cholesterol by 37%, doubling the dose reduces it by 43%. So we should think of grapefruit juice as an enhancer of Statins. Each reduction of LDL in the blood further reduces risk of heart disease.
The perception that grapefruit juice is contraindicated for people on statins is misleading and the conclusion from this study is that it can enhance the positive effects of these three statins. Grapefruits are low in calories and high in Vitamin A and C and with a low glycemic index they have a positive effect on blood sugar. This is good news for people who like grapefruit juice and who take statins.
There is no reason to avoid them.
(brand names are Zocor, Mevacor and Lipitor)