Does GUYABANO have significant anti-cancer properties?
Exaggerated by commercial websites, the potential anti-cancer benefits are shown only in laboratory in vitro experiments, with no clinical study so far
GUYABANO has been heavily touted in media circles as a deadly cancer killer, yet, the medical community remains critical of this claim, putting forth the fact that not a single clinical trial has ever presented such evidence. To begin with, no clinical trial has ever been conducted on guyabano at all.
Since the old days, the guyabano fruit (custard apple or sour sop in English), has figured prominently in the medical treatment of various illnesses among native Indians in South American countries. Grown from the guyabano or graviola tree (annona reticulate), the fruit—including its leaves, stem, roots, seeds, and bark— have been used to cure asthma, arthritis, heart and liver diseases. It is also said to lower blood pressure, strengthen the immune system, improve energy levels, heal wounds, eliminate worms, relieve diarrhea and fever, treat gonorrhea and herpes, among others.
Some sectors even push the envelope further by attesting to the fruit’s cancer-fighting capability. Several websites indicate this claim, stating that guyabano’s efficacy against several cancer types is 10,000 times stronger than that of the drug adriamycin, which is used in chemotherapy treatments for cancer. This is because various nonclinical experiments have shown that the tasty, fleshy fruit slows the growth of cancer cells.
According to these websites, the first scientific research to delve into guyabano’s supposed anti-cancer properties was conducted in 1976 by the National Cancer Institute in the United States . Researchers discovered that the leaves and stems of the fruit were effective in killing malignant cancer cells, but these were mainly laboratory studies.
Since then, around 20 more independent laboratory tests were undertaken and results have been remarkable: Extracts from the graviola tree were found to successfully inhibit the growth of malignant cells in 12 cancer forms including breast, prostate, colon, pancreatic, and lung cancers.
One of these studies was undertaken by the Catholic University of South Korea. Published in the Journal of Natural Products, the study yielded one particularly astounding discovery: The graviola tree was specifically on-target, correctly identifying cancerous cells in the body and bypassing the harmless cells-a complete deviation from chemotherapy which targets all cells that multiply, including hair and stomach cells, thus leading to hair loss and nausea which commonly afflict cancer patients.
Meanwhile, Purdue University in Indiana, United States, likewise performed research on annonaceousacetogenins— substances extracted from the graviola tree. Published in 2008, the research yielded similar findings: that these substances are potent inhibitors of cancer cells while leaving normal cells untouched and unaffected. The compounds also turned out to be effective against drug-resistant cancer cells.
With these purported health benefits circulating electronically and otherwise, some individuals suffering from cancer have actually drank the juice of the guyabano and credited the elimination of their illness to the fruit,rather than to modern medicine. Some have even revealed their complete cure of the illness even at its terminal stage.
The problem with the Purdue University experiment is that it was conducted in vitro, and not as a clinical trial. In fact, ever since 1976 when the National Cancer Institute first did research on guyabano’s anti-cancer functions, not a single double-blind clinical trial was ever mounted. Legitimate medical journals and doctors totally rely on clinical trials, rather than in vitro experiments, to judge the credibility of a proposed medical treatment.
Hence, the claim that guyabano is a powerful remedy against cancer has not been scientifically proven, prohibiting many doctors from recommending the fruit as alegitimate cancer cure.
In fact, the Philippine Society of Medical Oncologists, along with many other medical specialists, remains firm on their stand that modern medicine should be backed-up by strong scientific evidence. Neither the graviola tree nor its fruit has the strength of such evidence.
Curiously, some of those websites praising the guyabano are also promoting certain graviola-based products or supplements being sold by establishments which do not make an effort to undertake scientifi c research on the product. Angelica A. de Leon
VS, Vol. 2, Issue 20