Updated: Wed, 10/02/2024 - 13:45

From Saturday, Oct. 5 through Monday, Oct. 7, the Downtown and Macdonald Campuses will be open only to McGill students, employees and essential visitors. Many classes will be held online. Remote work required where possible. See Campus Public Safety website for details.


Du samedi 5 octobre au lundi 7 octobre, le campus du centre-ville et le campus Macdonald ne seront accessibles qu’aux étudiants et aux membres du personnel de l’Université McGill, ainsi qu’aux visiteurs essentiels. De nombreux cours auront lieu en ligne. Le personnel devra travailler à distance, si possible. Voir le site Web de la Direction de la protection et de la prévention pour plus de détails.

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What is soursop?

Either the fruit or the juice or teas made from the leaves of the tree on which the fruit grows have been anecdotally reported to help treat digestive problems, diabetes, asthma, fever and anxiety. Raising the red flag of skepticism is appropriate whenever such a wide range of claims is made on behalf of one particular substance.

Soursop is the fruit of a tropical tree, also known as custard apple, graviola or Brazilian paw paw. It’s a particular favorite in the West Indies and South America both for its tangy taste and its supposed medicinal properties. If you can think of a condition, chances are that someone will have reported that it can be treated with graviola. Either the fruit or the juice or teas made from the leaves of the tree on which the fruit grows have been anecdotally reported to help treat diarrhea, digestive problems, parasite infections, diabetes, asthma, colds, arthritis, high blood pressure, fever and anxiety. Raising the red flag of skepticism is appropriate whenever such a wide range of claims is made on behalf of one particular substance. The ailments described have a variety of causes and it is most unlikely they all respond to a single intervention. Our bodies just don’t work like that. Asthma and diabetes, for example, are unrelated and require different forms of treatment.

Of course with natural products such as graviola, there is always the argument that they are composed of hundreds of different compounds, and therefore it is possible that it contains some that may treat asthma and others that are effective for diabetes control. But a much more likely explanation is that the reported benefits are due to a blend of wishful thinking, the resolution of self-limiting conditions, unconfirmed anecdotes and of course that good old stand-by, the placebo effect. Dozens of other plants, fruits and herbs that grow in the Caribbean and South America have as rich histories as “cure-alls” as graviola. But folklore is not evidence, no matter how compelling some individual testimonials may sound. Especially when it comes to serious diseases such as cancer. And yes, graviola is supposed to cure that as well.

Why haven’t you heard about that? The “spine-chilling answer” at least according to the promoters of graviola supplements, “illustrates just how easily our health–and for many, our very lives–are controlled by money and power. Big Pharma, they claim, is doing everything in its power to keep this natural miraculous cancer cure under wraps in order to protect the enormous profits it reaps from its toxic chemotherapy drugs that do little more than poison patients. But luckily, those purveyors of natural cures, such as the Health Sciences Institute which is not any sort of Institute and has little to do with science, have been able to secure a “limited supply of Graviola extract grown and harvested by indigenous people in Brazil.” You can get the full Graviola story from the Institute if you care to peruse its brochure, “Beyond Chemotherapy; New Cancer Killers, Safe As Mother’s Milk.” Or you can view a video on the web, but you better do it quickly, you’ll be told, because they don’t know how long they will be able to prevent Big Pharma from shutting it down.

As is usually the case, what the graviolians have done is dredged the scientific literature to find some little grains of truth which they then managed to ferment into an intoxicating potion. And there is nothing more intoxicating, and marketable as a “secret cancer potion.” Those grains of truth were uncovered in some research carried out at Purdue University back in 1997. A number of compounds isolated from soursop, called annonaceous acetogenins, were tested for their ability to kill cancer cells in the laboratory. The focus was on a particular type of cancer cell that was resistant to the effects of common chemotherapy drugs like adriamycin. This is an uncommon situation but of great academic interest. It turned out that one of the compounds in graviola, bullatacin, was effective in killing the resistant cancer cells.

Such experiments are performed around the world all the time and thousands of compounds with such cancer cell-killing activities are known. But they rarely progress to anything substantive in terms of human treatment. All that such a finding means is that further studies are warranted to see if there is any effect in animals. If that can be documented then human trials may be indicated. But as far as graviola is concerned, nothing further has been published. Never mind human trials, there aren’t even any animal trials that have been published. And of course we don’t know whether graviola when used as a drug is free of side effects. But this has not prevented the energetic marketing of various graviola products with headlines such as “deadly conspiracy exposed.” The conspiracy of course is supposed to be by pharmaceutical companies that want to keep us from finding out about the graviola miracle. Soursop may be a delicious fruit, but the claims about cancer cure leave a sour taste in the mouth.

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