There isn’t only one way to treat cancer. Everybody is different and that means everybody’s response to various cancer treatments is different. By considering alternative therapies in addition to or in place of conventional treatment, you offer your body more options for hope and healing. 

Although a cancer diagnosis can bring with it a feeling of helplessness, remember—you are still in control. By understanding the array of treatments options available, you can decide how you want to move forward on your journey. If conventional treatment isn’t for you, you may want to consider one of the most popular non-invasive, alternative therapies—laetrile therapy.

What is laetrile therapy?

We’ll provide you all the information you need to know about this centuries-old alternative cancer treatment so that you can determine if it’s the right choice for you.

Breaking Down Laetrile Therapy

Although laetrile therapy was developed in the 1950s1, its main ingredient—amygdalin—has been used in cancer treatments since the 1800s.2 That’s because amygdalin is naturally sourced. It can be found in the seeds of certain fruits—including apricots, plums, cherries, and apples—as well as in raw nuts and plants like lima beans and clover. 

After amygdalin was isolated by scientists, it was used for cancer treatment through oral administration, typically in pill form. While the results were positive, work with amygdalin was essentially put on hold after more research showed it was potentially toxic. 

Amygdalin’s toxicity occurs when it’s digested and converted into hydrogen cyanide in the body. In fact, it’s this cyanide toxicity that’s believed to effectively kill cancer cells. While the body does have ways to protect itself from the toxic effects of cyanide in small doses, too much cyanide can lead to cyanide poisoning. 

That’s where laetrile therapy comes into the picture. 

How Does Laetrile Therapy Work?

Laetrile treatment is basically a man-made (or synthetic) form of amygdalin. It was developed so that amygdalin could still be used to treat cancer, but with a decreased risk of cyanide poisoning. 

The development of laetrile therapy also allowed amygdalin to be given intravenously instead of orally. Since the digestive system plays a significant role in converting amygdalin into cyanide, this further reduces the risk of cyanide poisoning. 

Although cyanide is believed to be an active factor in amygdalin’s anticancer properties, there are several theories as to how laetrile therapy works to kill cancer cells within the body. 

Hydrogen Cyanide for Cancer Treatment

When laetrile enters the body, it’s hydrolyzed into something called prunasin. This substance is then converted into mandelonitrile in the small intestine. From there, it’s broken down further into two key compounds—hydrogen cyanide and benzaldehyde. These are the two compounds believed to be responsible for killing cancer cells. 

When hydrogen cyanide comes into contact with cancer cells, it inhibits them from using oxygen. Without oxygen, cells can’t continue to grow and replicate. This means these cancer cells stop dead in their tracks.

Normally, the cells in your body contain an enzyme called rhodanese. Think of rhodanese as your cell’s persuasive negotiator. When confronted with cyanide, rhodanese makes an appearance, and convinces the cyanide to convert into a compound that’s harmless to your body. 

Fortunately, cancer cells are believed to be deficient in rhodanese. That means when cyanide confronts these cancer cells, they have no defense against it. What’s more is that cancer cells are also believed to have higher levels of beta-glucosidase and beta-glucuronidase. These are the enzymes that are responsible for breaking laetrile down into hydrogen cyanide. 

By having higher levels of these enzymes, cancer cells convert laetrile into cyanide faster than healthy cells would. In other words, not only do cancer cells have no defense against hydrogen cyanide, but they’re also essentially bombarded with it through laetrile therapy. 

Benzaldehyde for Cancer Treatment 

The second important compound derived from laetrile therapy is known as benzaldehyde. Studies have shown that this compound can have an analgesic effect, meaning that it can effectively relieve pain. 

However, benzaldehyde’s importance in cancer treatment lies in its ability to stop the activation and growth of particular cancer cells. This was determined through an important study conducted in 1980.3 During this study, 57 cancer patients were treated with benzaldehyde for an average of two years and five months. All 57 patients had previously been treated through conventional methods, but without success. They were all deemed terminal.

The results of the study were astonishing. According to data, 19 of the 57 patients had complete tumor remission after treatment, while 10 had partial remission of above 50%. Seven patients showed no signs of remission, however, they also showed no signs of progression. In fact, only two of the 57 patients saw progression of their cancer. 

Laetrile Therapy for Vitamin B17 Deficiency 

Another theory suggests that cancer may be caused by a deficiency in B17. Since amygdalin is a main source of this vitamin, it’s believed that laetrile therapy is useful in providing the body with the necessary B17 it needs to fight cancer cells. There are many B17 benefits that can contribute to the success of your cancer treatment. Check out our blog to learn more about the role of B17 and cancer

But amygdalin isn’t the only source of vitamin B17. Natural sources of B17 include:

  • Seeds – Apricot seeds are high in B17, but other seeds also contain the vitamin, including apple seeds, plum seeds, pear seeds, flax seeds, and squash seeds.
  • Berries – Not only do the tiny seeds found within berries contain B17, but the berries themselves also provide the vitamin. These include raspberries, elderberries, strawberries, blueberries, and blackberries. 
  • Nuts – Bitter almonds contain high levels of vitamin B17. Macadamia nuts and cashews offer the vitamin as well, but at a lower dose.
  • Grains and millets – Sorghum, buckwheat, and millet are all sources of B17. 
  • Sprouts – These include bamboo sprouts, alfalfa sprouts, and mung sprouts. 

Other Benefits of Laetrile Therapy

The benefits of laetrile therapy don’t stop at cancer treatment. In fact, the many ways in which laetrile therapy can aid the body is part of what makes it one of the most commonly used alternative therapies. 

The National Cancer Institute even performed a study that found many patients treated with laetrile therapy had significant symptom improvement. These patients reported that they were able to go back to performing daily activities they had previously put on hold due to their cancer symptoms.4 

What else can you expect to experience with laetrile therapy?

  • Reduced blood pressure – Studies have shown that amygdalin can lower systolic blood pressure by as much as 28.5% and diastolic blood pressure by as much as 25%.5
  • Enhanced immune system – Laetrile therapy can also increase white blood cell count. White blood cells are essential in fighting off infections and disease. 
  • Inflammatory pain relief – Studies conducted with animals have shown that amygdalin’s anti-inflammatory properties can significantly reduce pain. 

The Misrepresentation of Laetrile Therapy

Despite the many benefits of amygdalin and laetrile therapy, it was banned by the FDA in the 80s due to the concern over cyanide poisoning. However, much more research has been conducted since then, leading many states to lift this ban so that patients can receive treatment. 

New studies have shown that amygdalin can induce apoptosis—cell death—in leukemia cells, certain prostate cancer cells, and oral cancer cells. A 2019 study even suggests that laetrile therapy can be effective against breast cancer cells by inhibiting their growth.6

With this new research available, scientists can now take steps to perform controlled clinical trials to more fully understand the efficacy of laetrile therapy. This means directly comparing patients who’ve received laetrile therapy against patients who haven’t received the treatment. 

Side Effects of Laetrile Therapy 

Like any type of medical treatment, side effects are possible with laetrile therapy. Some of these side effects include:

  • Nausea and vomiting 
  • Headache
  • Dizziness 
  • Trouble walking
  • Low blood pressure
  • Fever 
  • Confusion
  • Drooping eyelids
  • Blue skin (due to lack of oxygen in the blood)
  • Liver damage

Many of these side effects can be avoided by ensuring the proper dosage of amygdalin is administered and a proper diet is followed. In some cases, side effects were worse when patients ingested high amounts of vitamin C or natural amygdalin sources while receiving treatment. 

That’s why if you’re interested in choosing laetrile therapy as a treatment option, it’s important to reach out to our doctors at Immunity Therapy Center. We can walk you through the process of laetrile therapy, and determine whether to combine treatment with a particular diet, supplements, or enzymes to best suit your needs. We’ll also thoroughly monitor your progress so that the risk of any negative side effects remains low. 

Renewed Hope with Laetrile Therapy 

With scientists and doctors conducting more research every day on alternative therapy options, there’s no need to feel confined to conventional forms of cancer treatment. Whether you decide to supplement conventional treatment with an alternative therapy, or focus entirely on the non-invasive therapy itself, the choice is entirely up to you. 

If you’re unsure whether laetrile therapy is the right treatment option for you, contact us. We’ve helped countless patients find success, even in the most advanced stages of cancer. With our help, you can reclaim control over your life and find hope in your healing. 


Written By: Dr. Adolfo Carrillo

Dr. Adolfo Carrillo is a Board Certified Medical Doctor from Universidad Autónoma de Baja California.

Dr. Carrillo has been collaborating with Dr. Bautista for over 5 years as a treating physician at the Immunity the Immunity Therapy Center. Dr. Carrillo is a charismatic Doctor whose knowledge and commitment to patient care and bringing healing to patients is a valuable asset to our center.



  1. NCBI. Laetrile treatment for cancer. 
  2. Cancer Research UK. Laetrile (amygdalin or vitamin B17). 
  3. National Cancer Institute. Laetrile/Amygdalin (PDQ)-Health Professional Version. 
  4. Healthline. Laetrile (Vitamin B17 or Amygdalin): Benefits, Myths and Food Sources.
  5. De Felippe Junior, “Benzaldehyde in Cancer – oxidant and strong structurer of cytoplasmic water with effect on several neoplasias.” 
  6. NDTV Food. Vitamin B17 Sources and Reasons To Not Skip Them.
  7. National Cancer Institute. Laetrile/Amygdalin (PDQ)-Patient Version. 
  8. NIH National Library of Medicine. Amygdalin from Apricot Kernels Induces Apoptosis and Causes Cell Cycle Arrest in Cancer Cells: An Updated Review.
  9. Heal Navigator. Vitamin B17 and Cancer Research.
  10. WebMD. Apricot Seeds for Cancer Treatment.
  11. Memorial Sloan Kettering Cancer Center. Amygdalin.
  12. Journal of Cancer Research and Therapeutics. Advanced research on anti-tumor effects on amygdalin.;year=2014;volume=10;issue=5;spage=3;epage=7;aulast=Song


March 15, 2021

Dr. Carlos Bautista is a Board Certified Medical Doctor. He received his Medical Degree from Universidad Autónoma de Baja California and has more than 20 years of experience working with Alternative Medicine to treat cancer, autoimmune diseases, chronic degenerative diseases, and infectious diseases. He opened Immunity Therapy Center in 2007 with the goal of providing the highest quality medical care for more than 5,000 patients.

At Immunity Therapy Center, our goal is to provide objective, updated, and research-based information on all health-related topics. This article is based on scientific research and/or other scientific articles. All information has been fact-checked and reviewed by Dr. Carlos Bautista, a Board Certified Medical Doctor at Immunity Therapy Center. All information published on the site must undergo an extensive review process to ensure accuracy. This article contains trusted sources with all references hyperlinked for the reader's visibility.