Does CBD Help Cancer?

According to the American Cancer Society’s Global Cancer Facts and Figures, there were 7 million new cancer diagnoses and 9.5 million cancer deaths around the world in 2018. These numbers are predicted to grow to 27.5 million new cancer diagnoses and 16.3 million cancer deaths by 2040.

And those projections only take into account the growing and aging population. These numbers could be even larger due to increases in cancer risk factors such as higher rates of smoking, unhealthy diet, and sedentary lifestyles in economically developing nations.

This represents a massive burden on the healthcare system. In the United States alone, over 1.7 million new cases of cancer are diagnosed every year. And the direct medical costs associated with cancer in 2015 were estimated to be $80.2 billion.

In addition to the financial burden, this disease also takes a huge toll on individual cancer patients and their families. A cancer diagnosis and the battle that follows can be physically demanding and emotionally overwhelming.

Cancer researchers continue to seek out novel ways to reduce these effects. One promising option is CBD. CBD, a non-psychoactive chemical compound found in cannabis, appears to provide a wide range of benefits for cancer patients. Studies show CBD relieves pain, chemotherapy-induced nausea, anxiety, and sleep problems. Early research indicates CBD may even cause or contribute to cancer cell death, leading many to view it as a potential anticancer drug. More research needs to be done, but for now, many cancer patients are turning to CBD oil as a way to alleviate symptoms of living with cancer and improve their quality of life.

Cancer: An Overview

Cancer is a broad term that applies to a large family of related diseases. All cancers are caused by the same essential process—a group of cells begins to divide uncontrollably and spreads to nearby, healthy cells. This process can occur in any part of the body.

Despite being made of trillions of cells, our bodies are able to tightly control the birth, growth, and death of every cell. But cancer removes the checks and balances that normally control cell growth.

Cancerous cells will continue to grow and divide while ignoring messages from their surrounding environment to slow down and stop. These out of control cancer cells can then spread into nearby areas and cause damage to healthy tissues.

What Causes Cancer?

Cancer is a genetic disease. This means the disease is caused by genetic mutations. In the case of cancer, these mutations are created in the genes that control how our cells grow and divide. Usually, more than one mutation is required for cancer to form. And each case of cancer has a unique set of genetic changes. 

The mutations themselves can either be passed down from our parents or arise from exposure to harmful environmental substances. Common risk factors that increase your likelihood of getting cancer include:

  • Age
  • Alcohol use
  • Tobacco use
  • Exposure to cancer-causing substances
  • Diet
  • Chronic inflammation
  • Obesity
  • Radiation
  • Excessive exposure to sunlight

While everyone’s risk for cancer increases with age, you can limit your chances of developing cancer by avoiding the above risk factors.

Treatment Options

The type of cancer treatment used will depend on the form of cancer and how advanced it has become. Additionally, most people will receive more than one type of treatment. Treatment options include:

  • Surgery: This procedure involves the removal of cancerous cells from your body by a surgeon. Sometimes surgeons can remove the entire bulk of a cancerous tumor, but even removing portions of the cancerous cells can help relieve painful symptoms and increase the success of other treatments.  
  • Chemotherapy: This method uses powerful medications to kill cancer cells.
  • Radiation: Radiation therapy uses high levels of radiation to damage and eventually kill cancer cells.
  • Immunotherapy: This method aims to boost your immune system so it can more successfully fight against cancer.

While advances in medical research have greatly improved the effectiveness of cancer treatments, most treatment options have unwanted, sometimes severe side effects. Chemotherapy, for instance, can potentially cause a long list of undesirable side effects such as mood changes, nausea, and vomiting.

What is CBD?

Cancer researchers and healthcare providers are still searching for new cancer treatments and remedies to help patients cope with the side effects of their current treatments. That’s where CBD comes in.

CBD is one of over 100 chemical compounds found naturally in the cannabis plant. These compounds are called cannabinoids, and they mimic the structure of the endocannabinoids your own body produces, as part of your endocannabinoid system.

The main function of the endocannabinoid system (ECS) is to keep your body in a state of balance. It helps regulate your mood, immune system, appetite, sleep, and pain response. The ECS does this by way of cannabinoid receptors located in your central and peripheral nervous systems. 

When endocannabinoids, or external cannabinoids like CBD, bind to these receptors, the interaction stimulates your ECS and helps bring the body back into balance. This is why CBD produces such a wide range of benefits, from pain and anxiety relief to reduced inflammation and nausea.


You may be wondering if CBD is the same as THC, another cannabinoid that comes from the cannabis plant. THC is well-known among the cancer community in the form of medical marijuana and is often prescribed to treat the negative side effects associated with cancer treatment.

Medical marijuana has brought relief to many people suffering from cancer. However, the FDA has not approved medical marijuana for cancer treatment. Despite this and its illegal status in many regions of the United States, oncologists still recommend medical marijuana to help with symptom management of treatment-related side effects.

There’s an unfortunate lack of research looking at THC and medical marijuana. But the research to date shows that medical marijuana is effective for treating anorexia, chemotherapy-induced nausea and vomiting, pain, insomnia, and depression. For some patients, it’s the only antiemetic (a drug that fights nausea and vomiting) that works. It’s also the only antiemetic that increases appetite.

While THC can be effective, it also has some drawbacks. The psychoactive properties of THC produce a feeling of being “stoned” that can interact with the individual’s ability to function normally. For some people, THC induces feelings of anxiety. There’s also the problem of legality with THC. Medical marijuana is only legalized in a portion of states, and users typically need a prescription.

CBD offers an excellent alternative to THC. This cannabinoid carries many of the benefits of medical marijuana (see ‘Benefits of CBD for Cancer’ below). But CBD is non-psychoactive—it does not create a “high” like THC. In fact, CBD actually counteracts the high of THC, reducing the feeling of being stoned, along with some negative side effects like anxiety or paranoia.

Additionally, CBD is legal in all fifty states and can be easily purchased online and in many local health stores. All of this makes CBD an attractive option for cancer patients seeking the same relief of medical marijuana, but without the high or potential legal obstacles.

Benefits of CBD for Cancer

CBD research is a new and growing field. Thus far, however, the results are promising—particularly for cancer patients. Specifically, CBD can help cancer patients cope with the side effects of treatment, such as chemotherapy-induced nausea, pain, and sleep issues. There’s also evidence that CBD may be able to slow or prevent cancer growth.

CBD provides chronic pain relief

Many individuals with cancer live with chronic pain. Cancer can cause pain as it invades and damages healthy tissue in the body. However, the treatments that target and fight cancer can also cause pain. Patients recovering from surgery often experience pain while healing. And those suffering from cancer may experience general aches, pains, and headaches on a more regular basis.

The medications most often prescribed for pain are opioids. These are highly habit-forming, which puts these patients at risk of addiction. They also have serious side effects, like sleepiness, constipation, nausea, and vomiting. Despite the risk of addiction and side effects, opioids are extremely effective at relieving pain. Unfortunately, some cancer patients are unresponsive to opioids.

The endocannabinoid system has been shown to be involved in regulating pain, with a role in every stage of the pain processing pathway. This means that compounds like CBD that stimulate the endocannabinoid system represent promising treatments for both acute and chronic pain. And research shows that CBD may be helpful in managing otherwise difficult to treat pain.

Plus, CBD doesn’t lead to dependence or tolerance. For those worried about putting themselves at risk of addiction, CBD can be a safer alternative.

CBD lessens chemotherapy-induced nausea and vomiting

Chemotherapy is one of the most effective ways to kill cancer cells to date. Unfortunately, extreme side effects are common, such as fatigue, hair loss, and chemotherapy-induced nausea and vomiting (CINV). In fact, CINV symptoms are so common—and so severe—that they cause up to half of patients to delay or quit chemotherapy entirely.

CBD has been demonstrated to suppress nausea and vomiting. With this antiemetic effect, CBD can significantly reduce CINV. One study treated patients with a daily oral spray, which contained either a placebo or a combination of CBD and THC. The CBD/THC spray was well tolerated and significantly increased the proportion of patients showing a complete response (no self-reported nausea or vomiting).

Further, two separate systematic reviews of over 30 trials have found that CBD is significantly more effective in controlling nausea symptoms than other common antiemetic medications.

CBD relieves anxiety and sleep problems

Some of the most common symptoms experienced by cancer patients include sleep problems. Typically, these present as chemotherapy-related fatigue, or some form of insomnia (difficulty falling or staying asleep). Problematically, poor sleep quality impairs the immune system’s ability to function, while also worsening mood and cognitive performance.

Fortunately, several studies have found that CBD improves sleep quality, by enabling patients to fall asleep easier and reducing their nighttime awakenings.

Sleep issues themselves are often linked to pain or anxiety, both of which are common among cancer patients. Estimates range, but roughly 20% of cancer patients have anxiety or depression. CBD can help with anxiety, too, by activating 5-HT1A receptors in the brain. This interaction appears to facilitate serotonin production, creating an antidepressant-like effect.

CBD may slow or suppress tumor growth

CBD may also slow or stop tumor growth, according to a number of studies. Two studies focused on breast cancer found that CBD killed cancer cells, or otherwise slowed the growth of metastatic breast cancer. Similarly, CBD appears to inhibit tumor growth for liver cancer and glioblastoma.  

In some cases, it appears that CBD does not directly suppress tumor growth. Instead, it helps by enabling the primary treatment to be more effective. For example, one study found combining CBD with radiation therapy made the drug more effective.

As a natural anti-inflammatory, some researchers believe CBD may also have a preventative effect. There appears to be a causal link between inflammation and certain types of cancer, so a CBD regimen could potentially lower one’s risk for thyroid, brain, and prostate cancers.

CBD linked to increased survival rates for pancreatic cancer

In arguably the most exciting finding to come out of CBD research, a 2018 study found that CBD may actually increase cancer survival rates. The five-year survival rate for pancreatic cancer is 5%. Researchers split a group of mice with pancreatic cancer into two groups. One was treated with chemotherapy, while the other received a combination of CBD and chemotherapy. The group that received CBD survived nearly three times longer than the chemotherapy-only group.  

cbd and chemotherapy increased survival rates among mice with pancreatic cancer

Researchers found that activating a certain cannabinoid receptor, known as GPR55, appeared to boost cancer cell growth in the mice. They also found that CBD was a GPR55 antagonist. When they combined CBD with Gemcitabine (“GEM” in the image above), one of the most effective drugs in treating pancreatic cancer, the CBD inhibited the receptor. As a result, the Gemcitabine was more effective in slowing tumor cell growth, leading to a three-fold increase in survival rates.

It’s important to remember that this study was conducted on mice. More research still needs to be done to explore the efficacy of CBD in increasing cancer survival rates for humans.

Is It Safe to Use CBD Oil for Cancer?

Generally, CBD is very safe and has few to no side effects. However, when side effects occur, they’re most commonly among people who are taking other medication. Even then, side effects are rare, but they may include tiredness, dry mouth, nausea, diarrhea, or changes in appetite or blood pressure.

Because cancer patients are more likely to be taking other medications to manage their cancer, it’s extremely important to speak with your doctor before using CBD. They can advise you as to whether the CBD may interact negatively with your drugs (some studies show it increases the hepatic concentration of some drugs, leading to liver damage).

How to Use CBD Oil for Cancer

There are four main ways to consume CBD oil. Each of these methods is equally effective. People choose one method over another, mostly based on personal preference.


CBD vape oils are designed specifically to be inhaled through a vape pen or vaporizer. Inhalation of CBD provides the fastest relief, as the CBD enters the bloodstream directly through the lungs. Many individuals prefer inhaling CBD as they find the physical act of inhalation relaxing, they want to feel the effects as quickly as possible, and they like that the vape flavors mask the natural earthy flavor of CBD.

However, it is important to note that the effects of CBD last the shortest amount of time with inhalation, between 2 to 3 hours vs. the 4 to 6 hours offered by other methods of ingestion. For longer-lasting relief, we recommend one of the three methods below.


CBD oil tinctures require the user to place drops of the CBD oil beneath their tongue. With this method, onset may take a little bit longer than inhalation, but it is still fairly quick (around 5 to 20 minutes). People prefer sublingual tinctures as they can enjoy CBD without any other additives (such as the natural flavoring of CBD vape oils or CBD gummies), the dropper makes precise dosing easy, and they work quickly.

Topical application

CBD oil can also be applied topically to the skin, through creams, lotions, and gels. With this method of application, the CBD will not enter your bloodstream. Instead, the CBD will engage cannabinoid receptors through the skin. Many people prefer CBD topicals for managing pain, as rubbing the CBD cream into their skin affords them the opportunity to give themselves a massage.

One downside to topicals is that this method is naturally less precise than other methods. However, CBD topicals will always come with clear instructions for how to apply the CBD for desired effects.

Oral ingestion

CBD oil can also be eaten, through CBD edibles or by adding CBD oil to food or drink. You can also swallow CBD capsules, which resemble traditional pills or softgels, or eat CBD gummies.

With oral ingestion, it can take 30 to 90 minutes before you start feeling the effects, since the CBD has to travel through your digestive system before it enters your bloodstream. However, many people still prefer to eat CBD as they like the flavors of CBD gummies or, on the other hand, the lack of flavor provided by CBD capsules.

How Much CBD Oil to Take for Cancer

While CBD provides many benefits, ease of finding the right dose is not one of them. Finding your dose is arguably the hardest part of using CBD. Also, because CBD is not yet regulated by the FDA, no official dosing guidelines exist.

Most people use between 1mg to 6mg of CBD for every 10 pounds of their body weight. You can find the recommended dose of CBD for your body weight here.

The exact dose varies, based on the person’s body weight, personal body chemistry, and the intensity of their condition. Due to the severity of their symptoms, cancer patients typically have to use a higher amount of CBD.

When taking CBD, remember that it can take up to 90 minutes to feel the effects with oral methods. With other methods, the effects should be felt almost immediately, within a handful of minutes at most. As you begin your CBD regimen, start with the lowest dose for your body weight and slowly increase from there until you find one that’s effective.

How to Buy CBD Oil for Cancer

While CBD itself is safe, the industry is new and not yet regulated. If you are interested in trying CBD oil, take the following steps to ensure you buy quality CBD oil.

  • Only purchase from manufacturers who use third-party labs to test the safety of their ingredients. Third-party labs will test both the concentration of CBD and other cannabinoids, as well as the safety of other ingredients in the CBD oil. Manufacturers should make these safety certificates easily accessible to consumers, either online or with the product packaging.
  • Only buy CBD products sourced from hemp, not marijuana. CBD oils can be sourced from either hemp or marijuana. However, marijuana is not legal in all fifty states, and it typically contains higher amounts of THC. CBD oils sourced from hemp will contain 0.3% THC or less, so they will not produce a “high” or show up on a drug test for marijuana.
  • Avoid synthetic CBD. Along the same lines, CBD should come from pure hemp and contain no synthetic ingredients. Synthetic CBD is more likely to contain toxic ingredients and cause extreme side effects. Instead, choose CBD products made from 100% industrial hemp, locally grown in the USA, that only contain other organic or natural ingredients.
  • Read online reviews. Manufacturers will share customer reviews on their website. Read through these, not only to ensure the safety of the product, but also to assess the efficacy of the product for cancer specifically. Many customers will share what they are using the CBD for. You can also ask questions in online forums, like the Cancer subreddit, CBD subreddit, Cancer Chat, or American Cancer Society forums.
  • Consult your doctor. CBD can negatively interact with other medications you may be taking. Your doctor can advise you as to whether it is safe for you to try CBD, and they may also be able to provide additional recommendations around dosing or specific methods of ingestion.

Additional Resources

There’s a lot to explore with CBD, from different types of products to how it helps relieve various conditions. Learn more at the links below.