Although they were thoroughly debunked in the 1970s as anti-cancer agents, products made from apricot pits continue to be aggressively marketed to unsuspecting patients, according to a recent report in BuzzFeed.
Do apricot seeds fight cancer? What is vitamin B17?
The idea that such products could fight cancer arose because apricot pits contain a substance called amygdalin, which is broken down by the body to produce hydrogen cyanide. Because of the levels of certain enzymes in cancer cells, hydrogen cyanide is particularly poisonous to such cells, according to one theory. Another theory holds that cancer is a result of a vitamin deficiency, and amygdalin – also known as vitamin B17 – can restore the body to health. Yet another theory claims that in damaging cancer cells, amygdalin boosts the immune system to fight cancer.
Laetrile, a synthetic version of amygdalin, gained popularity in the 1970s as a cancer treatment when taken in conjunction with a special diet, high-dose vitamin supplements, and certain proteins, according to the National Cancer Institute (NCI). But because of a lack of clinical research evidence that laetrile is effective against cancer, or can be used safely, it has not been approved by the Food and Drug Administration (FDA) as a treatment for cancer.
Laboratory research into laetrile has produced contradictory results. Two animal studies of amygdalin by the NCI reported no response when it was given alone or with an enzyme that activates the release of cyanide from amygdalin in the body. One study reported that amygdalin somewhat slowed the growth of colon cancer cells; another reported that prostate cancer cells’ response to amygdalin increased as the dose of amygdalin increased; another reported the same “dose response” trend in cervical cancer cells. Contrary results were obtained in a study in rats which found that amygdalin was not effective at treating, preventing, or delaying development of tumors.
In clinical research, no controlled clinical trials of laetrile – which would compare patients who received the drug with those who did not – have been reported, according to the NCI. Findings from only two trials involving amygdalin have been published:
- A phase I study in six cancer patients found that amygdalin caused very few side effects, although two patients who ate raw almonds while taking amygdalin developed symptoms of cyanide poisoning.
- In a phase II study involving 175 patients with breast, lung, colon, or other cancer, patients received amygdalin injections for 21 days and also took certain vitamins and pancreatic enzymes. In about half of the participants, cancer had grown by the end of treatment. It had grown in all participants seven months after completing treatment.
While amygdalin and laetrile haven’t proved safe or effective as cancer treatments, apricots themselves are a good source of Vitamins A and C, as well as potassium and dietary fiber, according to Livestrong.com.
“We recommend a ‘food first’ approach to nutrition,” says Stacy Kennedy, MPH, RD, CSO, LDN, senior clinical nutritionist at Dana-Farber. “Obtaining vitamins, minerals, and other health promoting nutrients from foods is generally a safer and more effective approach than supplements.”
Kennedy says apricots can be a healthy choice for plant-based nutrition as part of a well-balanced diet, but that dried fruits contain more sugar than their fresh counterparts. Aim for no more than ¼ cup of dried fruits per day and look for products without added sugars or preservatives, she says.