Summary:
Dr. Asma Dilawari, medical oncologist and medical director at Thyme Care, shares food safety risks for people living with cancer.
Dilawari and another oncologist identify skipping the wash step on produce, including before cutting or peeling, as a common mistake that raises infection risk particularly for people with weakened immune systems, which can include those undergoing cancer treatment.
The experts frame the guidance as risk reduction rather than fear of food, emphasizing simple habits like washing produce, reading labels, and general kitchen cleanliness.
If connecting the topic of oncology to “produce mistakes” confuses you, we get it: It does seem random at first. What does cancer have to do with fruits and vegetables, considering that eating a healthy diet actually lowers our cancer risk, and what are so many of us doing wrong with them?
Plus, when you brainstorm tips that oncologists might share, topics that come to mind might include foods that oncologists never eat (hello, carcinogens) or a body change that an oncologist would never ignore. That makes more sense, right? As far as produce-related no-nos (for everybody, really), some obvious examples include eating moldy fruit or ignoring the “dirty dozen” list, aka the produce items most contaminated with pesticides.
Undoubtedly, that knowledge is paramount—but it’s not everything. Similar to how dementia risk is seemingly randomly tied to poor oral health, one kitchen habit could be linked with with cancer.
More specifically, there’s a common thing people do with produce—perhaps because they’re busy or think it’s “fine”—that puts your health at risk (and can be especially dangerous for people who already have a cancer diagnosis). Read on for what that mistake is, the problems it can cause, how to avoid the issue and other cancer-causing food mistakes, all according to oncologists.
The Common Produce Mistake To Stop Making, According to Oncologists
Not washing your produce before eating it (or even cutting it) is a big error, doctors say.
“As an oncologist, my biggest concern is not that unwashed produce directly causes cancer, but that it can expose people, especially those with weakened immune systems, to infections,” says Dr. Najeeb Al Hallak, MD, a medical oncologist and co-leader of the Gastrointestinal and Neuroendocrine Oncology Multidisciplinary Team. “For patients receiving chemotherapy, stem cell transplant recipients and some patients with blood cancers, these infections can become much more serious and occasionally life-threatening.”
Dr. Asma Dilawari, MD, a medical oncologist, medical director at Thyme Care and a former medical officer at the U.S. Food and Drug Administration, agrees that the issue is the increased risk of infection.
“Fresh produce can have bacteria, viruses and other contaminants that come from various parts of the supply chain, from where the food is grown to when it reaches your kitchen,” she explains.
That can be especially concerning for cancer patients who are immunocompromised. Even if you don’t have cancer, it’s important to keep this in mind so you can put healthy habits into place and keep your loved ones safe.
How To Wash Produce Effectively
The good news is that washing your fruits and veggies is easier than you might think. Washing with water alone reduces the risk of infection, according to Dr. Dilawari.
But let’s break it down a bit more. Dr. Al Hallak recommends first washing your hands, then rinsing the produce with cool, running water before eating, cutting or peeling it. (Yup, even produce that’s cut or peeled needs to be washed first because the knife can transfer the bacteria from the outside to the inside.)
On that note, he shares common blunders. “Hot water is not necessary and can affect the quality of produce,” he says. “Soaps, detergents or chemical washes are not recommended because produce can absorb residues. The physical action of rinsing and rubbing is what removes most contamination.”
The next step depends on what you’re washing.
When you’re cleaning produce that’s firmer—such as apples, cucumbers, melons or potatoes—Dr. Al Hallak encourages gently scrubbing it with a clean produce brush. When you’re working with a leafy green, remove damaged outer leaves, rinse thoroughly and dry with a clean towel.
Certain populations may want to put a little extra work into this process for added safety.
“Washing with a small amount of white vinegar may also decrease the chance of pathogens,” Dr. Dilawari says. “If you are very immunocompromised, as some cancer patients are, especially with intensive treatments like stem cell transplant, it may be safest to eat produce you can cook or peel.”
With that said, she clarifies that “no household washing can eliminate all pathogens.”