Will grapefruit juice lower my blood pressure?

DEAR POPULAR PHARMACY: I have been taking amlodipine and benazepril for many years to lower my blood pressure. Two days ago I decided to stop the meds and try a grapefruit instead.

My early morning blood pressure was 143/90. This is normal since I hadn’t taken my medication in 24 hours. I then ate a grapefruit and less than an hour later my blood pressure was down to 128/83. This is a greater reduction than my medications offer.

So I’m going to ask my nurse practitioner if I can replace my medications with a grapefruit. Or why not eat a grapefruit twice a day?

A. Thank you for sharing the results of your experiment. Your nurse practitioner may tell you not to eat grapefruit or drink grapefruit juice the same day you take amlodipine. Your body uses an enzyme called CYP3A4 to metabolize this calcium channel blocker. Grapefruit may slow CYP3A4, which could, in theory, lead to increased blood levels of the drug. Although this may not seem like a meaningful interaction to most people, individuals vary and you might be sensitive to this reaction (Journal of Personalized Medicine, March 22, 2022).

Your one-day experience with grapefruit isn’t long enough to prove that this citrus fruit could replace your blood pressure medication. On the other hand, some data supports the hypotensive effect of grapefruit (Critical Reviews in Food Science and Nutrition, February 2017).

A fascinating randomized controlled trial published in the British Journal of Clinical Pharmacology (February 2021) reported that combining grapefruit juice with beet juice lowered systolic blood pressure. The researchers concluded: “Since the taste (of beet juice) was improved by grapefruit juice, this combination could be used as a dietary approach to improve blood pressure. »

You can learn more about other ways to control high blood pressure in our “Blood Pressure Solutions e-Guide”. This online resource is available under the Health eGuides tab on www.PeoplesPharmacy.com.

Q. I have been taking statins for over 11 years to lower my cholesterol levels. I have been taking pravastatin for several years.

I am middle aged and have low testosterone (less than 200), very low libido, poor memory, depression, lack of energy and back muscle pain which has affected my sleep . Overall, I feel much older than I am.

I stopped taking pravastatin after reading that most of these side effects could be caused by statins. A scan revealed that my arteries are clean. Now I feel much better and am wondering if I should have my testosterone checked again.

A. Statin-type cholesterol-lowering drugs can reduce testosterone (Brazilian International Journal of Urology, March-April 2024). However, most doctors believe that this effect is not clinically significant.

A new study published in the Annals of Internal Medicine (May 14, 2024) shows that low T levels (below 213 ng/dL) are associated with a shorter lifespan. Very low testosterone levels (less than 153) are linked to a higher risk of death from cardiovascular disease.

We encourage you to have your testosterone levels measured again to see if stopping the statin has made a difference. While you’re at it, ask your doctor about including a zinc test. Low levels of this essential mineral are also associated with reduced testosterone levels (Journal of Trace Elements in Medicine and Biology, March 2023). There is some evidence that statins may reduce blood zinc levels (Journal of Trace Elements in Medicine and Biology, September 19, 2005).

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In their column, Joe and Teresa Graedon respond to letters from readers. Write to them at King Features, 628 Virginia Drive, Orlando, FL 32803, or email them through their website: www.PeoplesPharmacy.com. Their latest book is called “The Best Mistakes Doctors Make and How to Avoid Them.”

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