Fact Check

Dandelion Root Kills 98% of Cancer Cells in 48 Hours?

Dandelion root is being studied for possible anti-cancer properties, but there's absolutely no proof it kills "98 percent of cancer cells in 48 hours."

Published Sept. 29, 2016

Dandelion root can kill 98 percent of cancer cells in 48 hours.
What's True

Anecdotal evidence suggests dandelion root may contain "anti-cancer properties" and has prompted some study into the subject.

What's False

No firm scientific or medical evidence supports dandelion root as an effective treatment for cancer.

On 21 September 2016, the Health Eternally web site published an article headlined "Scientists Find Root That Kills 98% of Cancer Cells in Only 48 Hours," proclaiming that:

According to Dr. Carolyn Hamm from the Windsor Regional Cancer Centre in Ontario, Canada, dandelion root extract was the only thing that helped with chronic myelomonocytic leukemia. This form of cancer typically affects older adults.

John Di Carlo, who at the time was a 72-year old cancer patient at the hospital, was sent home to live out his final days after all efforts failed to treat his leukemia. He told CBC News that he was advised to drink dandelion root tea as a last ditch effort. Perhaps it should have been the first option offered in his treatment plan, as his cancer went into remission only four months later! His doctors attributed this to the dandelion tea that he drank.

Recent studies have shown that dandelion root extract can work very quickly on cancer cells, as was evidenced in Di Carlo's case. Within 48 hours of coming into contact with the extract, cancerous cells begin to disintegrate. The body happily replaces these with healthy new cells.

No particular research of the type touted by the headline was referenced in the Health Eternally article, and although its wording suggested that the cited case and purported findings were recent, the article's text linked only to a single CBC news report published back in February 2012. That CBC reporting indicated only that researchers "hoped to test" dandelion root's potential as a treatment for one specific type of cancer, not that dandelion root had actually been established as an effective cancer cure:

Researchers hope to test dandelion tea on patients at a Windsor, Ont., clinic after it was found the roots of the weed killed cancer cells in the laboratory.

The promising research is being led by a University of Windsor oncologist, in association with the Windsor Regional Cancer Centre.

Dr. Caroline Hamm said dandelion root extract is unique, and is one of the only things found to help with chronic myelomonocytic leukemia.

The roots of the common dandelion were ground up and made into tea. According to researchers, early results show that the tea kills cancer cells in the lab.

Interest in dandelion root as a cancer-fighting substance was not new in September 2016, as the Memorial Sloan-Kettering Cancer Center has (among others) been looking at the plant since at least 2010. Sloan-Kettering's web site currently indicates that as yet no data support the claim of dandelion root as an effective cancer preventive or treatment:

Dandelion has not been shown to treat or prevent cancer.

Dandelion is used in traditional medicine to treat many ailments. Laboratory studies have shown that dandelion can kill certain bacteria and other microbes. It was also found to have anticancer properties in colon cancer, pancreatic cancer, leukemia, and melanoma cells, but studies have not been conducted in humans. Dandelion has estrogenic activity. It may increase the growth of hormone-sensitive cancer cells. Dandelion can also promote urination.

Laboratory studies have shown dandelion to have anticancer properties, but clinical studies have not shown this effect in humans.

As for the "cured" patient and the promise of dandelion root trials referenced in the February 2012 CBC report, a December 2015 update indicated that study was set to commence shortly (and as such, had not yet yielded results):

Dr. Caroline Hamm, a medical oncologist at the Windsor Cancer Centre in Windsor, Ont. who is leading the study [says] she's seen improvements in some patients who drink dandelion root tea purchased at health food stores,

"Most of the responses that I have seen are very short. but there's a signal there that I think is worthwhile of further investigation," she said.

Hamm expects the trials to start within the next month.

We were not able to locate any published research indicating dandelion root affirmatively demonstrated an anti-cancer effect in humans, much less any information from scientists suggesting it kills "98 percent of cancer cells within 48 hours." As with most bombastic cancer cure claims, the danger is not so much that people will attempt to use inexpensive and fairly harmless dandelion as a supplemental treatment while adhering to accepted protocols, but that patients averse to standard cancer treatments might opt for unproven "cures" in lieu of science-based therapies (allowing the disease to progress dangerously in the interim).

It's also possible that the patient who supposedly saw his leukemia go into remission due to his drinking of dandelion tea simply experienced a phenomenon commonly known as spontaneous remission (or regression), a rare but long-documented outcome wherein cancer resolves on its own. Hard data about its likelihood of occurrence are scant because cancer is infrequently left untreated.


Deardorff, Julie.   "Spontaneous Cancer Remission Rare, But Worth Study."     Chicago Tribune.   29 September 2014.

Lee, Jennifer.   "Cancer-Fighting Tea Set for Clinical Trials In Ontario."     CBC.   18 December 2015.

Jessy, Thomas.   "Immunity Over Inability: The Spontaneous Regression of Cancer."     Journal of Natural Science, Biology and Medicine.   January 2011.

CBC.   "Dandelion Tea Touted as Possible Cancer Killer."     16 February 2012.

Memorial Sloan Kettering Cancer Center.   "Dandelion."     21 September 2016.

Kim LaCapria is a former writer for Snopes.