PSA: Star Fruit and Kidney Disease

[iLander]

I was doing some research about our (stupid, annoying, always looks half dead) starfruit tree and I came across something I didn't know:

The starfruit has a high amount of oxalic acid. This is not a problem if you are in normal health. But if you have kidney disease (on dialysis, extremely ill, or near renal failure) a starfruit snack can kill you. This was on the National Institutes of Health site, so it's legit.

So. If grandma is in the hospital with kidney disease, DO NOT include starfruit in the fruit basket.

Spinach also has a high amount of oxalic acid, but I didn't find any mentions of it pushing the kidneys into renal failure.

That's my PSA, and something I didn't know.

I'm pretty sure everyone knows about grapefruit and high blood pressure meds, so not going into that one.

Picture of starfruit for reference, also called carambola. The pic is actually an unripe fruit, the ribs should be yellow and the fruit should be orange, but this is how they usually are in grocery stores. They can be eaten like this (scrape off green ribs) but they taste a lot sweeter when fully ripe.

 

[Phoenix]

Thank you, iLander, for posting this. I hadn't even heard of oxalic acid. I don't have any kidney issue but do eat starfruit and other veggies with oxalic acid (love spinach), so it's good to know.

 

[Dancing Fire]

Haven't eaten star fruit in years, but fresh Lychees... I can put away 2 lbs easily.

 

[iLander]

Phoenix: I had never heard of it either, and stumbled upon it in one line about Carambola tree care. Then I searched some more and apparently this is a known issue and many people have been killed. Oxalic acid is also used as a pesticide and a cleaning agent, in Extremely concentrated forms (you'd have to eat 100 lbs of starfruit to get that concentration).

DF: I like fresh lychees too, but they give me hives, so I can only sneak a tiny piece before I start to itch. It's a shame.

On Grapefruit: I decided to expand on it, what the heck: grapefruit will "switch off" your blood pressure meds, making them completely ineffectual. Don't eat it or drink the juice if you take those meds. Kinda makes you wonder what happened in the '70's when it was HUGE among dieters.

 

[Aoife]

Apparently it isn't actually the oxalic acid in the star fruit that is the problem, it's a neurotoxin in it that healthy people can excrete, but people with impaired kidney function can't.

Either way, it's probably better to avoid.

 

[Gypsy]

I love star fruit. It's wonderful in fruit salads. But yes, if you are not healthy it is a good think to avoid.

 

[tuhumom]

Very interesting discussion. As a former kidney disease sufferer, I know how frustrating it can be to find answers. Just wanted to share a link that helped me out a lot when I was struggling to get better.

Best of luck to everyone!

 

[LLJsmom]

Thank you iLander! My kids love star fruit and so does my Dad. Just good to know!

 

[partgypsy]

Phoenix: I had never heard of it either, and stumbled upon it in one line about Carambola tree care. Then I searched some more and apparently this is a known issue and many people have been killed. Oxalic acid is also used as a pesticide and a cleaning agent, in Extremely concentrated forms (you'd have to eat 100 lbs of starfruit to get that concentration).

DF: I like fresh lychees too, but they give me hives, so I can only sneak a tiny piece before I start to itch. It's a shame.

On Grapefruit: I decided to expand on it, what the heck: grapefruit will "switch off" your blood pressure meds, making them completely ineffectual. Don't eat it or drink the juice if you take those meds. Kinda makes you wonder what happened in the '70's when it was HUGE among dieters.

actually re: grapefruit, not quite. They will block the cytochrome p450 pathway, which is an enzyme pathways that actually clears the drug. Since the drug is not being cleared by the body, the blood pressure meds are MORE potent (like you took more of them). In either case a bad thing. The only reason I know this is that I have discovered I'm allergic to 3 drugs (in all cases an over sensitivity to them) and they all use the cytochrome p 450 pathway, which may be the problem for me.

http://www.nutritionandmetabolism.com/content/5/1/27