Grapefruit contains compounds that inhibit certain liver enzymes needed to break down medications and supplements in the body.
This article provides an in-depth look at supplements that should not be mixed with grapefruit due to potentially dangerous interactions.
We explore why grapefruit affects medication absorption and examine specific supplements to use caution with. Grapefruit is a tantalizing fruit with a bittersweet taste that can spice up any morning.
However, what many don’t realize is that humble grapefruit can cause dangerous interactions with certain medications and supplements. Let’s explore why.
Why Grapefruit Impacts Absorption
Grapefruit contains compounds that inhibit certain liver enzymes needed to break down medications and supplements in the body.
When these enzymes are deactivated, more of the drug enters the bloodstream instead of being metabolized. This leads to excessive buildup and heightened effects.
While this might seem harmless, increased absorption can cause major health consequences depending on the supplement.
For those taking prescription medications, be sure to consult your doctor or use a medical interaction checker before consuming grapefruit. Even small amounts of juice can trigger interactions.
Now let’s examine some of the main supplement and vitamin categories to avoid mixing with this bittersweet citrus fruit.
Statins: Increased Risk of Muscle Damage
Statins are cholesterol-lowering medications like atorvastatin (Lipitor) and simvastatin (Zocor). Consuming grapefruit while taking these drugs can cause high levels to accumulate, increasing side effects.
Muscle breakdown is one worrying outcome. A 2020 study found muscle injury markers were elevated by an average of 20% when grapefruit juice was taken with simvastatin versus simvastatin alone.
Yikes! No thanks to muscle damage from my morning fruit. Best to enjoy statins and grapefruit at separate times of the day.
Blood Pressure Medications: Greater Changes in Blood Pressure
Medications for hypertension also don’t mix well with grapefruit and its enzyme-inhibiting qualities. In one trial, people had three times higher blood levels of felodipine (Plendil) when paired with grapefruit juice compared to felodipine alone. Greater variability in heart rate and blood pressure was also observed.
Clearly, grapefruit has a profound effect on felodipine absorption. While convenient to take supplements and fruit together, it’s safer to properly space apart ingestion if you’re on blood pressure meds.
Other Interactions
Beyond muscle and blood pressure effects, grapefruit can amplify toxicity for certain supplements.
- Estrogen – Increased hormone absorption raises risk of breast cancer recurrence.
- Fexofenadine (Allegra) – More allergy medication absorbed, causing dizziness.
- Cyclobenzaprine (Flexeril) – Higher muscle relaxant levels associated with central nervous system side effects.
Check your medications against a grapefruit interaction checker to be safe. When in doubt, keep grapefruit separate from your prescription regimen.
The Takeaway
While delicious, grapefruit can cause critical interactions with many supplements if taken at the same time. From statins to blood pressure medications, excess absorption occurs when liver enzymes are deactivated.
To avoid problems, use a medical interaction checker app to verify grapefruit’s safety with your prescriptions. And if you notice unusual side effects, consider grapefruit as a potential culprit and notify your doctor.