A post on Facebook has made a number of claims about cucumber’s ability to kill cancer cells. This is mostly based on evidence that looks at one chemical present in cucumbers and its ability to kill cells in the lab and in mice, rather than any evidence showing that specifically eating cucumbers prevents cancer in humans.
None of the scientific papers cited in the post show that eating cucumber can prevent or treat lung cancer.
One study the author refers to looked at the effect of a chemical called cucurbitacin B (found in cucumbers, and other foods like pumpkins and gourds) on tumour cell growth in both cells in the lab and in mice. It found that cucurbitacin B on its own or in combination with a chemotherapy drug slowed the growth of tumour cells. But this doesn’t prove that this chemical in isolation would be effective at treating lung cancer in humans, and definitely doesn’t prove that eating cucumber has the same benefits.
The post also includes a claim that research from India has shown that “people eating cucumber every day had a remarkable 71% less risk for lung cancer.”
We were not able to find any papers that supported this claim. Fact checkers Science Feedback also wrote about this post, and following that, the post’s author contacted them with details of a study he was referring to, and updated his post to include this link.
As Science Feedback wrote, that study did not prove that eating cucumbers prevented lung cancer. It looked at the diets of several hundred people, including a group that ate certain types of green vegetables, including cucumber. It found that consuming these foods was associated with lower rates of lung cancer. The paper concludes that diet in general has a role in causing lung cancer, but the association is weak compared to the effect of smoking.