Grapes in a parcel of a vineyard protected by a mobile umbrella system using solar energy, in Rians, southern France. ( AFP / Nicolas Tucat)

Facebook posts falsely tout grape seeds as proven cancer cure

Copyright AFP 2017-2022. All rights reserved.

Social media posts claim that consuming grape seeds or grapeseed oil can cure cancer. But cancer specialists say supplements from the fruit are still being studied and there is not enough scientific evidence to support the claim, while US health regulators warn against purported cancer cures promoted on social media.

"They hid this seed for more than 100 years, because it can cure any cancer in just a few days," a January 24, 2022 Facebook post claims.

Screenshot of a Facebook post taken February 2, 2022

Similar posts can be found on Facebook here, here, and here

Alternative cures, unusual medications and even hazardous treatment advice for disease are often touted online, and cancer is no exception. AFP has previously debunked claims that some foods -- including lemon waterapricot seedshot pineapple water and dandelion root extract -- are effective cancer cures. 

The US Food and Drug Administration (FDA), warns consumers to "beware of products claiming to cure cancer on websites or social media platforms, such as Facebook and Instagram."

The FDA website notes that these unproven treatments come in many forms, "including pills, capsules, powders, creams, teas, oils, and treatment kits," and are "frequently advertised as 'natural' treatments and often falsely labeled as dietary supplements."

Dr Stacy D'Andre, a Mayo Clinic affiliated oncologist and integrative medicine specialist, told AFP: "Grape seed supplements are being studied for their anti-cancer potential, but there is no conclusive evidence that this supplement can cure or treat cancer."

"There is some anti-cancer activity seen in cell culture and animal models and early trials with prostate cancer patients, but more research is needed," she said.

The findings have also not been consistent across cancers. She explained that "one study showed that people who consumed grape seed had fewer blood cancers," but another found "grapeseed did not help breast cancer patients with the side effects of radiation therapy."

This was echoed by The Memorial Sloan Kettering Cancer Center, a New York treatment and research center. Its website says: "Although it has antioxidant properties, grape seed has not been shown to treat or prevent cancer." 

Dr Nagi Kumar, a senior member of the cancer epidemiology program and department of breast and genitourinary oncology at the Florida-based Moffitt Cancer Center, cautioned that there "is still more information needed about these promising compounds from grape seed products."

Kumar said early studies examining grape seed oil showed encouraging results, including "reduction in inflammatory and insulin resistance markers, which have an implication in obesity and thus cancer." 

But she said: "It is still unclear how long these compounds stay in the blood and how much of these compounds consumed really get into the blood of humans in order to provide these beneficial effects. Most of all studies in humans are still needed."

Dr Marji McCullough, the senior scientific director of epidemiology research for The American Cancer Society agreed. "Grape seed extract (GSE) is rich in proanthocyanidins which has antioxidant properties. However, the limited number of studies in humans have not shown that GSE can prevent or treat cancer."

"Proanthocyanidins are found in a variety of plant foods, including berries, apples, kidney beans, and nuts, and therefore can be part of a healthy, mostly plant-based diet," she added.

Both D'Andre and McCullough also warned that grape seed products can potentially interact with other medications. They recommend disclosing all supplements taken or considered to one's health care provider.