No research shows that dandelion can kill cancer cells or treat cancer in humans

Key takeaway

Many herbal products exhibit interesting medicinal properties in experiments conducted on animals or cells cultured in Petri dishes. However, clinical trials involving people are necessary to prove that a product is effective and safe as a treatment for a specific health condition. While a few studies using cell cultures and mice reported that dandelion extracts could reduce the survival or growth of cancer cells in the lab, there’s no clinical data indicating that it’s effective against cancer in humans.

Reviewed content

Verdict:

Unsupported

Claim:

Dandelion is able to “kill 98% of cancer cells within 48 hours”

Verdict detail

Misleading: The claim didn’t mention that there’s no scientific evidence of dandelion’s anticancer properties in humans. This can mislead users into believing that dandelion has been proven to treat cancer effectively.
Inadequate support: The claim didn’t provide scientific evidence showing that dandelion could kill most cancer cells in 48 hours.

See our method of evaluation

Full Claim

Dandelion is able to “kill 98% of cancer cells within 48 hours”; dandelion is an powerful treatment for cancer

A claim circulated on social media in May 2024 that dandelion is able to “kill 98% of cancer cells within 48 hours”, implying that dandelion is a potent cancer cure. The claim appeared on TikTok and Facebook, accruing more than 100,000 interactions.

This isn’t the first time this claim has circulated. It previously appeared on social media in 2021. At the time, Lead Stories and USA Today explained that the lack of context around social media posts containing the claim could mislead people, pointing out the absence of evidence of dandelion’s anticancer properties in humans.

Claims of potent health benefits of herbs and miraculous “natural” cures are legion on social media. Verifying their accuracy is important as these claims may encourage people to stop their prescribed treatments in lieu of untested products with unproven benefits.

Those claims quite often contain a grain of truth, because one can indeed find scientific publications reporting some effects of these products. However, they’re commonly misleading because they fail to acknowledge that the scientific evidence for these potential benefits is generally scant and limited to experiments in Petri dishes and test tubes. That is, there is little to no clinical data about how these products would work in humans. Science Feedback reviewed several claims of this kind in the past.

In the case of the claim analyzed here, there’s some research indicating that dandelion (Taraxacum officinale) may have some anticancer activity. However, to date, all of these results are from lab experiments in cell cultures or in mice.

In May 2024, we conducted a search on PubMed, a repository of biomedical publications maintained by the U.S. National Library of Medicine. We found 35 publications about the anticancer activity of dandelion^#. But none of them reported the results of human clinical trials.

Some studies showed that dandelion extract applied directly onto cancerous cells growing in a Petri dish could reduce their viability^[1,2]. Other studies that involved feeding mice with dandelion extracts found that the extracts could slow down the growth of human tumors implanted under the skin of the animals^[3,4].

USA Today reported that the specific figures of “98%” of cells killed “within 48h” figures may come from a 2016 study^[4] showing that dandelion extract killed 95% of colon cancer cells cultivated in a Petri dish within 48h. However, one of the study’s coauthors explained to the newspaper that it “does not mean a patient who takes dandelion root will be cured in 48 hours”.

Although these experiments in cell cultures and animals form an important basis for future studies in humans, on their own they can’t tell us whether a product provides health benefits to humans.

Firstly, a living organism is far more complex than a group of cells growing in a Petri dish. For example, cell cultures cannot answer several questions needed to determine whether a molecule or an extract is an effective treatment in humans. Such questions range from the ease of administering the treatment, to whether the treatment might interfere with other biological functions in unsafe ways, to whether the treatment can reach the tumor.

Secondly, even animal experiments—performed in living organisms and a step up in complexity compared to cell cultures—aren’t fully predictive of what happens in humans. This is why clinical trials on humans are necessary for drug and treatment development. It’s also important to note that 95% of cancer drug candidates fail to pass clinical trials^[5].

The Memorial Sloan Kettering Cancer Center also noted that:

“There have been a few case reports of potential benefit in patients with blood cancers, but it is unclear whether this was definitively due to dandelion supplementation. Clinical trials are needed to determine the conditions under which dandelion may be safe and effective.”

Likewise, the National Center for Complementary and Integrative Health, part of the U.S. National Institutes of Health (NIH) stated:

“We know very little about dandelion’s health effects. There’s little scientific evidence on this herb. […] There’s no compelling scientific evidence supporting the use of dandelion for any health condition.”

In conclusion, dandelion is yet another example of an herbal product that showed promising results in in vitro and animal experiments, but these effects haven’t been confirmed by clinical trials in humans so far.

NOTES:

# The Pubmed search query used was as follows: (dandelion[Title] OR “Taraxacum mongolicum”[Title] OR “Taraxacum officinale”[Title] OR “T. mongolicum”[Title] OR “T. officinale”[Title]) AND (cancer*[Title] OR tumor*[Title] OR anti-cancer*[Title] OR anti-tumor*[Title] OR anticancer*[Title] OR antitumor*[Title])

REFERENCES

• 1 – Li et al. (2022) Dandelion Seed Extract Affects Tumor Progression and Enhances the Sensitivity of Cisplatin in Esophageal Squamous Cell Carcinoma. Frontiers in Pharmacology.
• 2 – Li et al. (2017) Taraxacum mongolicum extract induced endoplasmic reticulum stress associated-apoptosis in triple-negative breast cancer cells. Journal of Ethnopharmacology.
• 3 – Nguyen et al. (2019) Dandelion Root and Lemongrass Extracts Induce Apoptosis, Enhance Chemotherapeutic Efficacy, and Reduce Tumour Xenograft Growth In Vivo in Prostate Cancer. Evidence-Based Complementary and Alternative Medicine.
• 4 – Ovadje et al. (2016) Dandelion root extract affects colorectal cancer proliferation and survival through the activation of multiple death signalling pathways. Oncotarget.
• 5 – Wong et al. (2019) Estimation of clinical trial success rates and related parameters. Biostatistics.