Can Apricot Seeds Cure Cancer?

Long before coffee enemas and shark cartilage were touted as miracle cancer cures, there were apricot seeds. The seeds, which contain a compound called amygdalin, have a storied history, with a range of uses in countries around the world going back centuries. But amygdalin hasn’t been shown to heal cancer.

Most people agree that research in cells has shown that compounds in apricot seeds may help to kill cancer. But when researchers studied the effects of apricot seeds on people with cancer, they found that it didn’t help fight cancer cells or improve symptoms. Eating apricot seeds can also cause cyanide poisoning and make you very sick. This is why many researchers recommend that people with cancer stay away from apricot seeds.

“You don’t want to take something that is not proven at all to reduce cancer and is known to have toxicity,” says Nancy Klauber-DeMore, MD, a breast cancer surgeon at the Medical University of South Carolina who studies natural products for treating cancer. 

But others believe that members of the government and scientists have knowingly suppressed research of laetrile for their own gain. More than 50 years ago, the author G. Edward Griffin wrote a book called World Without Cancer; The Story of Vitamin B17, in which he described laetrile as “the final answer to the cancer riddle.” You can see echoes of this book all over social media today. 

Apricot seeds are used in traditional medicine to treat a variety of conditions. People in the U.S. didn’t think about using them to treat cancer until the 20th century. In the 1920s, a doctor named Ernst Krebs suggested that amygdalin reduced tumors in mice. But he also said it was too unpredictable and dangerous for humans to take.

In the 1950s, Krebs’s son followed in his father’s footsteps and made a version of amygdalin that he called laetrile. Ernst Krebs, Jr., said laetrile was safer for humans than amygdalin, but the main component of laetrile is amygdalin. The younger Krebs also called the compound vitamin B17 and suggested that people with low B17 levels were at greater risk of cancer. (Scientists have not accepted B17 as a real vitamin.) You may hear people use the term amygdalin, laetrile, B17, or a combination of all three when referring to the component found in apricot seeds.

The way that amygdalin is said to fight cancer is by releasing cyanide, which cancer cells may be more sensitive to. But healthy cells can still be damaged by cyanide.

More than 70,000 people in the U.S. used amygdalin throughout the 1970s. But the Food and Drug Administration (FDA) banned laetrile in 1979 after people began experiencing symptoms of cyanide poisoning after eating amygdalin. An article published in 2018 describes people who were harmed by eating apricot seeds, laetrile tablets, and more. The European Union has also banned its use. 

However, the FDA doesn’t regulate the sale of apricot seeds or extract because these products are dietary supplements, not medicines. People can easily find and purchase them. In 2024, the FDA warned the public about apricot seeds being sold online that contained toxic levels of amygdalin. Because these products aren’t regulated, they can be contaminated with other potentially dangerous drugs.

Amygdalin isn’t just found in apricot seeds. It’s also found in the pits of peaches, raw nuts such as bitter almonds, lima beans, clover, and sorghum.

Like with most medicines, research on amygdalin started out in studies of cells in labs. These studies were promising, as the drug did kill cancer cells. However, the concentration of amygdalin that the cells were exposed to was a level that would be toxic to humans, explains Skyler Johnson, MD, a radiation oncologist at the University of Utah who studies non-traditional cancer treatments. Just because something kills cancer cells in a dish in a lab doesn’t mean it’ll work when tested in animal studies or in clinical trials.

So researchers began to test amygdalin in animals, such as mice and rats. A review by National Cancer Institute experts shows that out of seven animal studies, only one found that amygdalin killed cancer cells — in this case, cervical cancer cells. The other studies did not find that amygdalin damaged or killed cancer cells.

Scientists have also tested amygdalin in humans. The first study was done in six healthy people to test the drug for dosage and toxicity. It was deemed safe enough for a larger trial in people with cancer. The researchers then tested laetrile in 178 people with cancer — 21 of whom had breast cancer. They didn’t find any benefit to cancer growth, symptoms, or lifespan. A few people in the study experienced symptoms of cyanide toxicity, had blood cyanide levels approaching a deadly level, or both. The authors of the study, which appeared in The New England Journal of Medicine in 1982, concluded, “Amygdalin (Laetrile) is a toxic drug that is not effective as a cancer treatment.”

It’s important to note that there are case reports of people with cancer improving after taking amygdalin. However, these one-off reports don’t prove that amygdalin is effective. 

“You never know in one person what was responsible for curing the cancer, because there’s always a possibility that something could happen by chance,” Klauber-DeMore says. “That's the problem: People hear stories of one person, and then they assume that it was due to the natural product that they were taking,” she says. 

Large studies are needed to prove that positive results are due to taking amygdalin rather than something else that people who take it are doing for cancer treatment.

As amygdalin breaks down in the body, it becomes cyanide. If you have too much cyanide in your body, you may experience cyanide poisoning. The most common side effects of cyanide poisoning are nausea, vomiting, breathing issues, headache, heart palpitations, skin discoloration, and reduced alertness or consciousness. Symptoms of cyanide poisoning can also include liver damage, nerve damage, fever, coma, and death.

Some evidence suggests that being treated with laetrile through an IV (directly into a vein) rather than by mouth can reduce toxicity. That’s because giving it by IV avoids the digestive system, where amygdalin is changed into cyanide, Klauber-DeMore explains. It may be useful for scientists to study whether IV laetrile could help fight cancer without bad side effects, she says. But without more clinical trials, taking IV laetrile could still be dangerous and isn’t supported by evidence.

Klauber-DeMore says she’d like to see more research of natural products to see if they can help with cancer treatment or managing symptoms. But she doesn’t think it’s a good idea for people to switch from standard treatments like chemotherapy and radiation to natural products, she says. “They could be missing the opportunity to take medication that could really help them.”