As a renal dietitian, I’m a big fan of allowing as many foods as possible in each of my client’s diets.
I never want to tell them to not eat something, especially since food is such a big part of our lives and enjoyment. Almost all foods can be included, no matter the health conditions.
But this is a hard rule for me.
What is star fruit?
Star fruit, also known as averrhola carambola, is a sweet and tangy fruit that is, well, shaped like a star. It has a slightly bitter taste at times with an edible skin.
While star fruit is not a common part of the American diet, it is more prevalent in the Asian, Filipino, and other tropical diets.
Star fruit is also a MUST to avoid if you have any sort of kidney disease or damage.
Some people believe in star fruit benefits for diabetes. This, however, has not been medically or scientifically proven yet.
Star Fruit Nutrition
One medium star fruit contains (1);
6 grams of carbohydrates
2.5 grams of fiber
9 milligrams (mg) magnesium
121 mg potassium
But what is also contains – and this is the most important thing – is a kidney toxin.
Star fruit contains a neurotoxin called caramboxin that can be filtered by fully-functioning kidneys, but can cause further kidney damage and other health issues if you have any kidney damage. (2)
If it cannot be filtered by the kidneys, the toxin collects in the blood stream and results in neurological issues.
Symptoms of star fruit toxicity may include:
DEATH in serious cases
Consuming the fruit whole or as a juice is not recommended at all as it cannot be safely processed and eliminated for those with kidney disease or damage.
Some cases have even shown those with fully functioning kidneys develop acute kidney damage/failure after drinking or eating star fruit.
If you have a higher risk of kidney disease, it may be in your best interest to limit or avoid star fruit.
Fruits that are good for your kidneys
There are plenty of other fruits that are more than healthy and beneficial for your kidneys.
Two of the nutrition benefits of including fruit in your renal diet are to control blood pressure and blood sugars – two things that if left uncontrolled can do a lot of damage to your kidneys.
Fruits safe for kidney disease;
And so many more!
These are examples of lower-potassium fruits, but keep in mind you are likely able to include more high-potassium fruits in your diet as well.
Just keep in mind – no star fruit!
Star fruit toxicity: a cause of both acute kidney injury and chronic kidney disease: a report of two cases. R. A. Abeysekera et al. BMC Res Notes. 2015; 8: 796. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4683968/
Association of renal function and symptoms with mortality in star fruit (Averrhoa carambola) intoxication. Chua SB et al. Clin Toxicol (Phila). 2017 Aug;55(7):624-628. https://www.ncbi.nlm.nih.gov/pubmed/28443386