The Truth behind Three Natural Cancer “Cures”

Cannabis oil is often heralded as an alternative cure for cancer

Cannabis oil is often heralded as a treatment for cancer and other diseases, but there’s no science to support these claims.

The Internet is full of “miracle cures” for cancer and alleged surefire ways to prevent it, and well-meaning people may urge cancer patients to just try them out in hopes of eliminating their disease. Some patients, worried that conventional treatments won’t work or pose significant side effects, seek a treatment whose effectiveness isn’t actually supported by scientific evidence or may even prove dangerous. During a time of uncertainty and anxiety, it’s understandable that any hope for a cure — even if it isn’t medically proven — is tempting.

“Patients want something ‘natural’ to try to treat their cancer or prevent their cancer from coming back,” says Memorial Sloan Kettering pharmacist and herbalist K. Simon Yeung. “But the people promoting these treatments might not necessarily have a medical or oncology background. In addition, patients who try these therapies may find, when they come back to seek mainstream treatment, that it’s too late and their cancer has already spread.”

Dr. Yeung is manager of the About Herbs database, created and maintained by MSK’s Integrative Medicine Service. The service provides complementary therapies such as acupuncture, music therapy, and massage that are used in addition to — not as alternatives for — mainstream cancer approaches such as chemotherapy, radiation, and surgery.

Here, Dr. Yeung explains the hype and the scientific evidence surrounding three highly publicized but unproven therapies: cannabis oil, Laetrile, and a pH-manipulation (also known as alkaline) diet.

Cannabis Oil

The hype: Cannabis oil is often heralded as a treatment to destroy or shrink cancerous tumors, as well as a cure for diabetes, ulcers, arthritis, migraines, insomnia, infections, and many other diseases. Also called marijuana oil or hemp oil, it’s extracted from marijuana plants, often with higher proportion of a compound known as CBD (cannabidiol), which has less of a psychoactive effect than the more-famous THC (tetrahydrocannabinol) compound that gets marijuana users high.

Cannabis oil is available in several forms with different potencies. It can be infused into cooking oil that users squirt under the tongue or mix into food. Its vapors can also be inhaled. By federal law, cannabis products are illegal, though several states have enacted laws to legalize their medical use.  

The evidence: While commercially available cannabis compounds are FDA-approved to reduce cancer treatment–related side effects such as nausea and vomiting and to improve appetite, no clinical trials have shown that cannabis products can treat cancer.

Claims that cannabis oil cures cancer are anecdotal and largely unsupportable, based on scant research done in mice and in labs. Side effects can include memory and attention loss. Perhaps most important, there is evidence that cannabis compounds may inhibit enzymes that patients need to metabolize other anticancer drugs, thereby increasing their toxicity or reducing their effectiveness.   

The verdict: “So far, there are no human studies that show cannabis oil can be used as cancer treatment,” Dr. Yeung says. “Patients who are using it — or any form of marijuana — should let their doctors know so they can advise you properly.”

Back to top


The hype: Laetrile, first popularized as a cancer therapy in Russia and the United States more than a century ago, is the trade name for a purified form of amygdalin, an extract derived from apricot pits and some nuts and plants. Intestinal enzymes break down Laetrile to produce cyanide, which proponents claim kills cancer cells and leaves normal tissue unharmed. Some also claim that Laetrile is actually a vitamin called B-17 and that deficiencies can cause certain cancers. Banned in the United States, an oral form of Laetrile is available in other countries.

The evidence: Laetrile indeed breaks down into cyanide, but the poison doesn’t just selectively strike cancer cells — it can sicken or kill patients as well. Clinical studies done in the 1970s and 1980s, including those sponsored by the National Institutes of Health, indicated that Laetrile didn’t reduce malignant tumors’ size or growth, but some patients experienced cyanide poisoning.   

The verdict: “Laetrile has not been proven to be effective against cancer and can even be dangerous to some patients,” Dr. Yeung says. “If amygdalin is eventually used in an anticancer drug, it will have to be in a different form, because the oral form is toxic and too dangerous to use.”

Back to top

Manipulating pH Levels through Diet

The hype: Based on the scientific observation that cancer cells thrive in an acidic environment — meaning low pH levels — some people contend that highly “acidic” foods such as meat, cheese, and grain products raise the risk of cancer by reducing pH levels in the blood. They claim that eating “alkaline” foods such as fruit, green vegetables, and other plant-based products discourages the growth of cancer cells by raising blood pH levels and tout the benefits of the alkaline diet (also known as the alkaline ash diet or alkaline acid diet).

The evidence: Cancer cells create an acidic microenvironment due to a high metabolic rate. Cancer cells can’t live in a highly alkaline environment, but neither can healthy cells. Your body works to keep pH levels constant, and changing your diet is not going to substantially change the pH levels of your blood, which are tightly regulated by the kidneys and lungs regardless of foods consumed.

The pH of bodily fluids, such as saliva and urine, does change temporarily depending on the foods you eat, but that doesn’t affect blood pH levels (or, hence, the environment of cancer cells in the body). In fact, any significant deviation in blood pH levels can cause serious, even life-threatening conditions known as acidosis (low pH) or alkalosis (high pH)

The verdict: “There is no evidence that changing your diet to alter pH levels affects cancer growth,” Dr. Yeung says. “The actual science has been misinterpreted. Changing the pH in your saliva doesn’t mean your blood pH changes. Some patients try using chemicals to modify their blood pH, but that can be extremely dangerous.”

Back to top

The Bottom Line

“Natural” cancer therapies should be regarded with great caution because most are unsupported by evidence. Many people offering testimonials to the effectiveness of such treatments may attribute benefits to them simply because their condition improved after using them — when the actual cause for the improvement is unrelated.

The good news is that mainstream cancer therapies are safer and more effective than ever. New chemotherapies work better with fewer side effects, and novel drugs target specific mutations in cancer cells to minimize harm to healthy cells. Highly precise forms of radiation therapy destroy tumors while sparing normal tissue. New approaches harness the body’s own immune powers to destroy cancer cells. And new surgical techniques are making it possible to remove tumors more safely while minimizing both risk of recurrence and recovery times.  

If you’re considering using a complementary therapy in addition to your traditional cancer treatments, always check with a reputable source such as our About Herbs database or the National Cancer Institute, and always tell your doctor.

Back to top


Commenting is disabled for this blog post.

Dear Yosen, if you have cancer, it’s important to discuss the use of any supplements with your medical team. Thank you for your comment and best wishes to you.

Has anyone heard of IP-6 & Inositrol. Lots of research backing it. In my opinion because my sons and I have Li fraumini syndrome...and 2 of my 3 sons have been diagnosed with cancer...sarcomas. and my oldest just passed away from his 3rd fight with cancer and they all went with the traditional chemotherapy....and I've seen how uneffective it really is...and now I have been diagnosed with pleomorphic sarcoma in my abdomen...I want to stay as far away from that poison as I can. I've seen what it does first hand.

Dear Stephanie, we are very sorry for the loss of your son. We’re also sorry to hear that you and another son have also been diagnosed with sarcoma. There are very few scientific studies showing that inositol is effective against cancer, and there have been no controlled clinical trials in humans. You can learn more about the compound here:…

If you are interested in coming to MSK to learn more about treatment options, including the possibility of being treated with targeted therapy or immunotherapy, you can call 800-525-2225 or go to for more information on making an appointment. Thank you for your comment, and best wishes to you and your family.

My father has gastric cancer with advanced metastasis to liver. He underwent chemotherapy for six months last year and in the end the doctors found the disease to be stable, but the disease relapsed later and now they don’t find him strong enough to get chemo or immunotherapy. Since they haven’t left us any other options but to wait, we’re willing to try alternative supplements (CBD oil and turmeric). Would that be something that we should still be concerned about (especially since he’s not on drugs and therefore there would be no drug/herb complications)?

Dear Mehmet, we’re very sorry to hear about your father. Unfortunately, there have been no controlled trials that have shown CBD or turmeric is effective against cancer. We recommend that you discuss the use of any herbal treatments with his medical team, because some of them can have side effects. Thank you for your comment, and best wishes to you and your father.

When answering a question about herbal treatments I often here you and the Medical cumunity in general say “we don’t have any proof that this or that herba is affective on cancer! My question is, why aren’t trail studies done? Why only drug studies? Why not Herbal studies? Why not Natural substanceses? Do you have any studies coming up on Natural Cures? If not why not? I would be very interested in being part of one. Why are we, the ones who do not want traditional treatments be left to try to figure it out on our own? Do you not care for us? You could be the Leader in this field! You know Humany would that you for that, and so would I. Be a Hero!!
Thank you :)

I’m just curious if anyone has tried essiacs tea? I’m part of a group on FB and so many members have had such great success with this. I know it must have the whole sheep sorrel including the root. That and along with other things. It has been a long time cute per say and I believe Sloan Kettering hospital has some sort of research or we’re recommending it also. Google essiacs Tea. I know 2 brands that are recommended. Just Tea and blue moon. Or google Rene caissse. Look for the FB group called essiac Tea. There are so many things actual real people are doing. Not just for cancer either.

I am undergoing treatment for prostate cancer after having thyroid cancer 5 years ago. I also have an undiagnosed condition that prevents me from exercising or working, as I have a host of symptoms, including vertigo, joint pain, headaches, tinitus, brain fog, and back pain. All feel very inflammatory based, as does my cancer. I have taken mountains of blood tests, that the traditional MDS say don't reveal anything. I have also gone to holistic practitioners who have plied me with supplements, at a massive cost, that have yielded no results. So while I am all for trying things outside the traditional medical channels, the alternative world is full of charlatans and snake oil salesman promising cures that never come. As much as the often valid accusation that traditional doctors are beholden to big pharma, I have to wonder why holistic practitioners rarely take ANY insurance? And charge exhorbitent fees, both for their services and their supplements. I'm considering a very well reputed one who charges 750$ for the first consultation. Who is he beholden to? His wallet obviously. I'm all for looking outside the traditional medical community but beware.

Yes, my wife has MS as well as being diagnosed this week with Stage 4 Melanoma. We are getting ready to start opdivo yervoy for melanoma. We are no longer on any MS Medications. We are trying to get her immune system prepared for the treatments while trying to still keep her strong minus MS medications. Do you have suggestions on Vitamins and food styles to assist? We are truly trying to get control of our roller coaster, it's out of control. Thank you for any advice.

Dear Don, we’re sorry to hear about your wife’s diagnosis. Unfortunately, we are not able to offer medical advice on our blog. If she would like to come to MSK for a consultation, you can make an appointment online or call 800-525-2225. Thank you for your comment and best wishes to both of you.

A traditional western medical ($$ driven) organization will not champion a position that counters their own. This site is biased. They determine the natural methods are inconclusive but fail to conduct experiments of their own. How many natural options have mskcc tested in their research to fight cancer? Instead of saying "there is no study...", you guys have all the resources to conduct one. Why dont you?

Dear Dirk, MSK has an active program in integrative medicine research. You can learn more about our approach on this page. We also maintain an About Herbs database, where we compile the latest research on many herbs and supplements.Thank you for your comment.

Does taking CBD oil help people with cancer

What hope is their for a family member just diagnosed with an aggressive stomach cancer - GIST? They are trying desperately to get into MSK.

We’re very sorry to hear about your family member’s diagnosis. To arrange a consultation with a GIST expert at MSK, you can make an appointment online or call 800-525-2225. Thank you for your comment and best wishes to you and your family.

It's unfortunate that there are not more large scale clinical studies of THC, CBD and the endocannabinoid system with regard to various cancers. Some significant, positive results have been obtained by various small scale amateur and professional experiments.
But loosely referring to all the different possible active agents in the Cannabis plant and the different combinations as "Cannabis Oil" does not do justice to field. A little more research/knowledge sharing might help uncover some strong healing potential.