Zucchini Poisoning Is a Thing—Here's Why it Happens and How to Avoid It
Can you get seriously sick, or even die, from eating zucchini? A recent case report highlights the danger of cucurbitacin poisoning, a rare but potentially fatal condition connected to gourds
fcafotodigital / Getty Images
- Zucchini may seem harmless, but a recent case study of a patient with cramps, vomitting, diarrhea, and liver damage after eating zucchini shows the dangers of cucurbitacin poisoning.
- Cucurbitacin poisoning is a rare but potentially fatal condition caused by consuming a high level of cucurbitacins, a toxic compound that can form in plants in the gourd family.
- The benefits of zucchini still outweigh the risks, experts say, but throw away any bitter-tasting zucchini—as bitterness is the only known signifier of cucurbitacins.
Most of us don’t think of zucchini, the star of side dishes and baked goods, as dangerous to eat. But as it turns out, the popular squash can be toxic in rare instances.
A 2024 study published in the Polish Archives of Internal Medicine highlighted such a case. It involved a 54-year-old relatively healthy woman who ended up in a Czech Republic emergency department with severe abdominal pain accompanied by vomiting and bloody, watery diarrhea. The next day, doctors found she had liver damage.
Puzzled by why an otherwise healthy patient would develop such intense, sudden symptoms, the medical team tried to pinpoint a cause. One clue emerged: The patient recalled consuming unusually bitter zucchini bread before developing symptoms. Doctors eventually diagnosed her with cucurbitacin poisoning, caused by toxic compounds that can form in zucchini and other plants in the Cucurbita family.
“Cucurbitacin poisoning occurs when these compounds disrupt cellular processes, causing tissue irritation, particularly in the gastrointestinal tract,” Babeta Čápková, MD, case study co-author and a general medicine physician in the department of Internal Medicine at Tomas Bata Hospital Zlinin in the Czech Republic, told Health. “A bitter taste is indeed a hallmark of high cucurbitacin concentrations and often the only immediate indicator.”
Before you throw your zucchini in the trash, know that this type of poisoning is uncommon and not always serious—but that doesn’t mean you shouldn’t know the warning signs. Here’s what you need to know about cucurbitacin poisoning, as well as how safe it is to chow down on zucchini.
What Is Cucurbitacin Poisoning?
Cucurbitacins are organic compounds known as tetracyclic terpenes. Due to the compounds’ bitter taste, it’s believed plants produce them as a protective defense mechanism, Ryan Marino, MD, an associate professor of emergency medicine and psychiatry at Case Western Reserve University School of Medicine, told Health.
“While many plants produce terpenes, cucurbitacin is produced mainly by cucurbits—also known as gourds and gourd-like plants—like cucumbers, squash, and melons, although it and similar compounds can be found in many plant species and even some animals and fungi,” Marino said.
Plants can also produce cucurbitacins in response to environmental stress, such as suboptimal growing conditions like drought, Čápková explained.
While the compounds have been shown to be pharmacologically effective against inflammation, cancer, atherosclerosis, and diabetes, they can be toxic when ingested through food.
“Studies have shown that toxicity levels range between 2 and 12.5 milligrams per kilogram,” Čápková said. (That’s about 0.9–5.6 mg per pound.)
Whether someone develops symptoms after eating plants with cucurbitacins can depend on the amount consumed and individual tolerance and health, Čápková pointed out.
It’s not just zucchini that can cause severe cucurbitacin poisoning; the most commonly documented cases involve eating or drinking the juice of bottle gourds, a condition referred to as “toxic squash syndrome.”
Symptoms of Cucurbitacin Poisoning
Though cucurbitacin poisoning isn’t fully understood, experts believe the compounds disrupt the gastric lining, leading to vomiting, diarrhea, and bleeding. It can also have detrimental effects on the vascular system.
Symptoms of cucurbitacin poisoning typically come on suddenly within minutes to hours after consumption. Even tiny amounts can cause symptoms. In a Netherlands case study reported at the 2024 International Congress of the European Association of Poison Centres and Clinical Toxicologists, a couple became severely ill after the woman took one bite and the man took two bites of a casserole containing bitter-tasting zucchini grown in their garden.
In the majority of cases, cucurbitacin poisoning causes mild pain or gastrointestinal upset and doesn’t require medical care, explained Marino. Severe symptoms, such as those seen in case reports, are rare and can include nausea, vomiting, cramps, and diarrhea, said Čápková. Edema in the intestinal wall and abdominal organs and hypotension (low blood pressure) may occur in severe poisoning cases.
There is no antidote for cucurbitacin poisoning, and treatment focuses on managing symptoms, Marino said. Most patients with severe symptoms recover within a few days, although abdominal discomfort may linger slightly longer, Čápková said. (The Czech case study patient was nearly symptom-free after three days.)
In very rare cases, cucurbitacin poisoning can be fatal. While one of the patients in the Netherlands recovered fully, the other died less than 24 hours after eating the poisonous zucchini.
Diagnosis Is a Challenge
Cucurbitacin poisoning can be hard to diagnose for several reasons—the condition is rare, there’s no lab test to detect the toxins’ presence, and symptoms can mimic acute gastric illness.
That makes a thorough patient history critical to diagnosis, Marino said. “The most important feature in identifying potential cucurbitacin toxicity would be a report of ingesting one of the plants that produce it shortly before developing symptoms, usually with an abnormally bitter taste,” he said.
“Bitterness is detectable at concentrations of approximately 0.1% to 0.5% of the plant’s fresh weight, though this can vary based on environmental and genetic factors,” Čápková said.
However, many patients and physicians aren’t aware of the plants' poisonous potential for plants. When the Polish Archives of Internal Medicine patient eventually mentioned she had eaten the zucchini, doctors diagnosed her only after a nurse recalled learning that bitter zucchini shouldn’t be eaten, leading the medical team to consult online resources and a toxicology center.
“Accurate patient history is critical in these cases. However, awareness of cucurbitacin toxicity among physicians is limited, leading to misdiagnosis,” Čápková said. “Increasing education and awareness about this condition could improve diagnostic accuracy.”
Should You Skip Zucchini?
Zucchini and other plants with high levels of cucurbitacin don’t look, smell, or feel any differently than those without high levels. That makes bitter taste the only sign of potential toxicity.
If you consume a plant that tastes bitter, Marino advises getting medical care—but only if you develop symptoms. “The majority of people who are exposed likely do not become sick enough to need hospital-level care,” he said. “But if there is any concern, I would not hesitate to seek expeditious medical care.”
Does this mean you need to give up your favorite zucchini dip, sauce, or bread? Thankfully, the answer is no.
“The health benefits of eating these vegetables far outweigh the risks,” Čápková said. “There’s no need to avoid them, but you should taste them before cooking.”
If you taste any bitterness? “The rule is simple,” Čápková said. “Stop eating it and discard it.”
This story originally appeared on: Health News - Author:Cathy Nelson
