Misleading: Herbal products are regulated as dietary supplements, not as drugs. Most of them haven’t been tested for safety and efficacy against specific conditions, in which case one can’t claim they prevent, treat, or cure any disease.
FULL CLAIM: “There is a cure to every d!isease”; herbs can cure cancer, diabetes, Alzheimer’s
Chronic diseases comprise a wide range of conditions, including cardiovascular disease, cancer, diabetes, and Alzheimer’s disease, which are among the leading causes of death and disability worldwide. About 60% of adults in the U.S. and 35% in the European Union have a chronic condition.
While chronic diseases typically have no cure, desperate patients and their relatives may nevertheless turn to the Internet in the hopes of finding a remedy that helps them manage their symptoms. Thus, they become targets for health misinformation in the form of “miracle” cures and therapies that spread extensively online.
One instance of that type of misinformation is a Facebook reel published on 6 November 2023 claiming that herbs can cure “every disease”, from cancer to diabetes and Alzheimer’s. The reel was viewed more than 200,000 times and received over 10,000 interactions.
However, most herbal products haven’t been tested in clinical trials, in which case there’s no reliable evidence in humans that shows they prevent, treat, or cure diseases, as we will explain below. In the best-case scenario, such products might be ineffective. But some can pose health risks owing to side effects, interactions with medication, or by diverting patients from effective medical treatments.
Natural products sold as dietary supplements aren’t intended to treat diseases
For example, compounds derived from artemisinin, a chemical found in sweet wormwood (Artemisia annua), are recommended by the World Health Organization to treat malaria. Taxol, a chemical extracted from the bark of the Pacific Yew (Taxus brevifolia) tree, is now a chemotherapy drug used to treat several types of cancer.
But herbal products don’t cure chronic diseases. In an email, a spokesperson for the U.S. National Center for Complementary and Integrative Health (NCCIH) stated:
“Plants have been sources of medicine for millennia, and several effective pharmaceuticals including taxol and artemisinin originated from plants. Despite that history, it is completely false to claim any herbs have been proven effective treatments for any disease. It’s also important to note that in the United States it is illegal to claim a product sold as a dietary supplement can be used to treat any disease including symptoms associated with them.” [emphasis added]
You can read the NCCIH’s statement in full here.
Douglas A. Kinghorn, professor of medicinal chemistry and pharmacognosy at Ohio State University, explained in an email to Health Feedback, “[T]he only agents that can be used effectively to treat chronic diseases are those that have undergone substantial clinical trials. In some cases, such pure compounds are of plant origin”.
Indeed, natural products are chemically complex and typically contain multiple active ingredients that can have different effects on the body. For a natural product to become an effective drug, researchers first need to identify the chemicals responsible for the pharmacological effect of interest.
Then, they need to isolate these chemicals and study them in laboratory settings to understand their mode of action and potential risks. If the results from these studies are positive, the isolated compounds enter clinical trials to ensure they are safe and effective in patients. Only then can these compounds receive FDA approval for treating a disease.
However, the vast majority of natural products don’t follow this process because the FDA regulates herbal and other natural products as dietary supplements, not as medicines.
The NCCIH explained to Health Feedback:
“The difference between a drug and a dietary supplement is that the FDA has clear guidelines and requirements to establish the purity, safety and efficacy of a drug, and the FDA evaluates that information to make sure those requirements are met before it can be sold to consumers. This does not happen for herbal medicines in this country”.
This difference in regulatory policies means that natural products are largely untested and many of their proposed uses rely on tradition, cultural beliefs, and anecdotes, but often have little or no scientific evidence to support such use. Therefore, these products cannot replace medical treatment, as the NCCIH highlighted.
“When used properly, supplements can be used relatively safely to help with certain vitamin and mineral insufficiencies or to support a variety of what are known as ‘structure function’ activities. They should never be used as a substitute for pharmaceuticals for the treatment of any chronic condition.”
Natural doesn’t necessarily mean safe
A common feature in many natural products falsely promoted as treatments is the appeal to nature: specifically that because the product is “natural”, it must be “good” or harmless. Many contrast the “natural” quality of these products with the “artificiality” of drugs, which are framed as “bad” and cause side effects.
But the belief that natural products are necessarily innocuous is both false and dangerous. Natural doesn’t necessarily mean safe, and nature offers plenty of examples of compounds that are toxic and potentially deadly, especially when used excessively.
One point often overlooked about natural products is that they contain active ingredients, just like prescription drugs. And, like drugs, these ingredients can have both beneficial and harmful effects on health. Therefore, while most supplements are relatively safe when used properly, they can also carry certain risks.
In addition to any side effects that the active ingredient may cause, some natural products also have the potential to interact with medications. As a result, they can make a treatment less effective or even trigger unexpected side effects, which can be particularly serious in people with certain medical conditions.
Also, the NCCIH noted that some products “don’t contain the ingredient on the label, or contain additional adulterants not listed on the label”. Contamination with heavy metals, such as lead, mercury, arsenic, iron, and zinc is particularly concerning as studies have found unacceptable levels of these chemicals in many herbal products. Even at low concentrations, heavy metals can cause health problems, including gastrointestinal issues, liver and kidney damage, and neurologic problems.
But one of the most important risks associated with natural products is that they can provide a false sense of security that might lead some patients to delay or reject effective medical treatments. Doing so increases the risk of potentially life-threatening complications from the disease.
What is the scientific evidence behind the remedies mentioned in the reel?
In the first place, it is important to remember that chronic conditions such as cancer, diabetes, and Alzheimer’s have currently no cure, and the FDA states that products claiming otherwise are “a cruel deception”.
The reel listed several products that have been falsely promoted as cures for a wide range of diseases in the past. For example, bitter melon (Momordica charantia), soursop (Annona muricata, also called graviola and guanabana), Chaga (Inonotus obliquus) mushroom, and grape seeds, have been repeatedly touted as cancer cures. Coconut oil has also been widely promoted as a cure for Alzheimer’s.
In addition, the reel mentioned calaguala (Polypodium Leucotomos), cuachalalate (Amphipterygium adstringens) and wereke (Ibervillea sonorae), three plants traditionally used in Mexico to treat diabetes.
Donald I. Abrams, an integrative oncologist and professor emeritus at the University of California San Francisco, told Health Feedback in an email that the natural products listed in the reel “do not cure any diseases”.
He added he knew of “no raw botanical that ‘cures’ cancer, although the internet and social media are loaded with such claims by people that lack information from controlled clinical trials and often, sadly, are trying to take advantage of desperate people”. [Read Abrams’ comments in full here.]
Indeed, while these products have shown some promise in test tubes, laboratory cell cultures[3,4], and animals[5,6], evidence about their effectiveness in humans is lacking or very limited for all of them.
Studies on the lion’s mane (Hericium erinaceus), an edible mushroom used in traditional Chinese medicine, are slightly more advanced. Laboratory studies showed that compounds isolated from this mushroom promote neuron growth and connectivity, improving memory in mice[7,8].
Two small clinical trials found that consuming this mushroom was associated with improved performance in cognitive tests in people with mild cognitive impairment[9,10]. However, these results don’t mean that lion’s mane is an effective treatment for Alzheimer’s, as larger clinical trials are needed to confirm these findings.
Without robust clinical trials showing that these products are safe and effective in humans, claims that they can prevent or treat—let alone cure—chronic conditions are unsupported.
Furthermore, some of these products have shown signs of toxicity. One example is soursop, whose fruit, leaves, and stems contain neurotoxic alkaloids that are associated with neurological problems[11,12].
Abrams pointed out that researchers are currently investigating many other products whose benefit as adjuvants of conventional treatment has much more clinical support. Adjuvants are used alongside conventional treatment, but don’t replace it:
“As an integrative oncologist, there are a number of botanicals and fungi (Chaga and other medicinal mushrooms do not count as plants as they are in their own Kingdom) that I recommend to the patients I see in consultation. Some of the non-edible medicinal mushrooms, especially Trametes versicolor (Turkey tail), have been well-studied as immune enhancing adjuvants to conventional cancer therapies.”
Chronic conditions such as cancer, diabetes, and Alzheimer’s have currently no cure, contrary to the reel’s claim. The idea that specific natural products can treat or cure these conditions aren’t only false but also dangerous. In addition to possible side effects, these products can also cause drug interactions and may contain harmful adulterants or contaminants.
The role of nature as a source of new potential drugs is indisputable. But for natural products to become medicines, the compounds responsible for the beneficial effects need to be identified, isolated, and adequately tested.
While some natural remedies might benefit patients under certain circumstances, they cannot replace medical treatment. Using unproven therapies instead of effective medication increases the risk of disease complications and might reduce the patient’s chances of survival.
Statement from the NCCIH Press Office on behalf of pharmacognosist and deputy director of extramural research Craig Hopp:
Plants have been sources of medicine for millennia, and several effective pharmaceuticals including taxol and artemisinin originated from plants. Despite that history, it is completely false to claim any herbs have been proven effective treatments for any disease. It’s also important to note that in the United States it is illegal to claim a product sold as a dietary supplement can be used to treat any disease including symptoms associated with them.
The difference between a drug and a dietary supplement is that the FDA has clear guidelines and requirements to establish the purity, safety and efficacy of a drug, and the FDA evaluates that information to make sure those requirements are met before it can be sold to consumers. This does not happen for herbal medicines in this country. Consequently, there are risks associated with using herbal medicines sold as supplements. There are numerous examples of products that either don’t contain the ingredient on the label, or contain additional adulterants not listed on the label.
When used properly, supplements can be used relatively safely to help with certain vitamin and mineral insufficiencies or to support a variety of what are known as “structure function” activities. They should never be used as a substitute for pharmaceuticals for the treatment of any chronic condition.
Donald I Abrams, Professor, Department of Medicine, University of California San Francisco :
Herbs is a funny term. I think botanicals is probably better, as herbs call up culinary products.
As an oncologist, I can say botanicals have yielded a number of chemotherapeutic agents—the vinca alkaloids from periwinkle (vincristine and vinblastine) and the taxanes from the yew tree (paclitaxel and docetaxel)—that are effective in the treatment of malignant diseases.
However, I know of no raw botanical that “cures” cancer, although the internet and social media are loaded with such claims by people that lack information from controlled clinical trials and often, sadly, are trying to take advantage of desperate people.
As an integrative oncologist, there are a number of botanicals and fungi (Chaga and other medicinal mushrooms do not count as plants as they are in their own Kingdom) that I recommend to the patients I see in consultation. Some of the non-edible medicinal mushrooms, especially Trametes versicolor (Turkey tail), have been well-studied as immune enhancing adjuvants to conventional cancer therapies.
If you look at the NCI PDQ Integrative, Alternative and Complementary Therapies posting on Prostate Cancer, for example, you will find an extensive list of botanical supplements that have been studied as complementary therapies.
Integrative medicine integrates these complementary therapies with conventional treatments. Alternative therapies are used instead of, as opposed to with, conventional therapies and if they worked, why wouldn’t they become conventional therapies?
The natural products listed in the reel do not cure any diseases.
- 1 – Newman (2022) Natural products and drug discovery. National Science Review.
- 2 – Luo et al. (2021) Heavy Metal Contaminations in Herbal Medicines: Determination, Comprehensive Risk Assessments, and Solutions. Frontiers in Pharmacology.
- 3 – Ray et al. (2010) Bitter Melon (Momordica charantia) Extract Inhibits Breast Cancer Cell Proliferation by Modulating Cell Cycle Regulatory Genes and Promotes Apoptosis. Cancer Research.
- 4 – Torres et al. (2012) Graviola: A novel promising natural-derived drug that inhibits tumorigenicity and metastasis of pancreatic cancer cells in vitro and in vivo through altering cell metabolism. Cancer Letters.
- 5 – Youn et al. (2009) Potential anticancer properties of the water extract of Inontus obliquus by induction of apoptosis in melanoma B16-F10 cells. Journal of Ethnopharmacology.
- 6 – Chen et al. (2014) Grape Seed Proanthocyanidins (GSPs) Inhibit the Growth of Cervical Cancer by Inducing Apoptosis Mediated by the Mitochondrial Pathway. PLoS One.
- 7 – Lee et al. (2014) Protective Effects of Hericium erinaceus Mycelium and Its Isolated Erinacine A against Ischemia-Injury-Induced Neuronal Cell Death via the Inhibition of iNOS/p38 MAPK and Nitrotyrosine. International Journal of Molecular Sciences.
- 8 – Martinez-Marmol et al. (2023) Hericerin derivatives activates a pan-neurotrophic pathway in central hippocampal neurons converging to ERK1/2 signaling enhancing spatial memory. Journal of Neurochemistry.
- 9 – Li et al. (2020) Prevention of Early Alzheimer’s Disease by Erinacine A-Enriched Hericium erinaceus Mycelia Pilot Double-Blind Placebo-Controlled Study. Frontiers in Aging Neuroscience.
- 10 – Mori et al. (2008) Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment: a double-blind placebo-controlled clinical trial. Phytotherapy Research.
- 11 – Gustavo (1988) Tropical myeloneuropathies revisited. Current Opinion in Neurology.
- 12 – Caparros-Lefebvre et al. (1999) Possible relation of atypical parkinsonism in the French West Indies with consumption of tropical plants: a case-control study. The Lancet.