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Author Topic: Carambola and Renal Issues.....your thoughts  (Read 1087 times)


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Carambola and Renal Issues.....your thoughts
« on: February 10, 2012, 01:55:40 AM »
Its interesting to read that there are reports of "star-fruit" toxicity, mostly in pt's with already decreased renal function, but at the same time what is the limit on ingestion in pt's with normal renal function? This question alone bugs me. How much is too much?

I usually enjoy a star fruit at a time, but I'm sure if I had a profusely fruiting tree I would be encouraged to juice much of my fruit and therefore drink a lot, but could it be harmful?


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Re: Carambola and Renal Issues.....your thoughts
« Reply #1 on: February 10, 2012, 02:17:42 AM »
If i had impaired kidney function i would not eat starfruit, or any other fruit or vegetable with oxalic content. The amount of starfruit you can eat safely is going to depend on the maturity of the fruit and type of fruit. Obviously the sour types have a lot more oxalic acid. But most of us don't grow them, we're growing sweet types. One thing you can do to lower oxalic content is to trim any green parts off the fruits. Usually it is the ribs of the fruits that can remain green, so when juicing i trim all of those green ribs off.
If you have normal kidneys i don't think you're going to have any problems eating starfruit. We certainly have consumed massive quantities of them over the years, and drank many gallons of starfruit juice, and have no kidney problems or kidney stones. I don't think eating well ripened starfruits is any worse than eating rhubarb or spinach for the kidneys.


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Re: Carambola and Renal Issues.....your thoughts
« Reply #2 on: February 10, 2012, 11:24:59 AM »
Oxalic  acid ingestion is not linked, significantly, to the formation of kidney stones.
When the article are talking about renal impairment , they don't mean kidney stones since the overwhelming majority of people with stones have absolutely normal function.  Decreased function is documented with abnormal creatinine clearance ( basic blood tests show this) so if a doctor has never mentioned this, you are safe. 


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Re: Carambola and Renal Issues.....your thoughts
« Reply #3 on: March 17, 2012, 08:16:07 PM »
When your pee turns white cloudy, you have overdone it!   Such as when you forget your lunch a so do a variety-eating test of about 15 large carambolas.


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Re: Carambola and Renal Issues.....your thoughts
« Reply #4 on: March 18, 2012, 08:27:35 PM »
To the OP:
I would advise you to ask your doctor about your renal function if you are concerned.  I don't know your age, but a very significant number of older folks have moderate renal impairment and yet have a normal or very minimally elevated creatinine level.  Some docs may note this but not necessarily mention it to the patient.

Interesting article.  I took a peek at a couple of other related ones.  The mechanism for this toxicity is not known, but does not appear to have anything to do with oxalic acic or nephro/ureterolithiasis (kidney stones).  One article mentions a suspected "excitatory neurotoxin."  Scary as hell, really, with a significant mortality rate.  Bottom line, if your renal function is normal, you probably have no worries but if you have moderate or worse renal impairment (estimated GFR < 60) you should be careful.


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