Grapefruit vs Guava – Which is Healthier?

Our Verdict

When comparing grapefruit to guava, we picked the guava.

Why?

It’s not close:

In terms of macros, guava has 3x the fiber, slightly more carbs, and 3x the protein, winning easily in this category.

In the category of vitamins, grapefruit has more vitamin A, while guava has more of vitamins A, B1, B2, B3, B5, B6, B7, B9, C, E, and K, sweeping its second round in a row.

Looking at minerals, grapefruit has a tiny touch more calcium, while guava has a lot more copper, iron, magnesium, manganese, phosphorus, potassium, selenium, and zinc, winning its third round by a long way.

One more consideration that’s not shown in the nutritional values, is that grapefruit contains high levels of furanocoumarins, which can inhibit cytochrome P-450 3A4 isoenzyme and P-glycoptrotein transporters in the intestine and liver—slowing down their drug metabolism capabilities, thus effectively increasing the bioavailability of many drugs manifold.

This may sound superficially like a good thing (improving bioavailability of things we want), but in practice it means that in the case of many drugs, if you take them with (or near in time to) grapefruit or grapefruit juice, then congratulations, you just took an overdose. This happens with a lot of meds for blood pressure, cholesterol (including statins), calcium channel-blockers, anti-depressants, benzo-family drugs, beta-blockers, and more. Oh, and Viagra, too. Which latter might sound funny, but remember, Viagra’s mechanism of action is blood pressure modulation, and that is not something you want to mess around with unduly. So, do check with your pharmacist to know if you’re on any meds that would be affected by grapefruit or grapefruit juice!

PS: the same substance is quite available in pummelos and sour oranges (but not meaningfully in sweet oranges); you can see a chart here showing the relative furanocoumarin contents of many citrus fruits, or lack thereof as the case may be, as it is for lemons and most limes).

Adding up the sections makes for an overwhelming overall win for guava, but by all means do enjoy either or both, unless any of the furanocoumarin contraindications apply!

Want to learn more?

You might like:

Watch Out For Furanocoumarins!

Enjoy!