“This fruit can end your life!” says the email I got last week about balimbing (scientific name: Averrhoa carambola, family: Oxalidaceae, starfruit, bilimbi, carambola.) I thought it’s such an alarmist post that I need to comment. Besides, the exotic edible fruit traditionally carries a bad name in Philippine politics.
Vilified in our native Filipino language because of its curious shape and tarty taste, balimbing is a unique tropical fruit and a butt of jokes. Eaten raw, or used in fruit juices and salads, it’s equated with turn-coatism, flip-flopping, and lack of loyalty that’s common among traitors and politicians. The attractive star-shaped balimbing with its edgy sides and shiny yellow-green skin (fancied by fruit-faddists worldwide,) is therefore maligned and rejected. But the fruit isn’t that bad.
There are of reports though that balimbing harbors a neurotoxin that causes hiccups, seizures, numbness, psycho-motor agitation, confusion, nausea, vomiting, weakness and other neurologic signs and symptoms. With no correlation between the severity and amount ingested, the manifestations typically occur about 30 minutes to 6 hours after eating the fruit. Treatable by dialysis, the manifestations show in patients with impaired renal function, especially among those with renal failure. Because of the yet-to-be-identified toxin, people with failing kidneys, must not eat the fruit. (Nephro Dial Transplant (2003) 18: 120-125.)
Balimbing’s toxicity is ascribed to a suspected neurotoxin that crosses the blood brain barrier and accumulates in the body when not properly excreted in the urine. Without much scientific basis, some say it’s perhaps the oxalic acid content of the fruit that’s causing the trouble. Others theorize that the toxin is a potent inhibitor of the cytochrome p450 pathway in cellular metabolism which bring recall another fruit—this time the grapefruit’s inhibitory effects of certain medications.
However, since its first cultivation and consumption in Sri Lanka, Malaysia, South Pacific, the Philippines, and other parts of Asia, to my knowledge, balimbing is safe to eat by people who aren’t ill. There are limited documented scientific studies from Brazil and Hongkong that the fruit isn’t good for those with renal disease, but normal people can eat it without trouble. =0=