Divide some laboratory rabbits into three groups. Feed one group normal rabbit chow, the second group a high-cholesterol diet and the third a high-cholesterol diet supplemented with 0.2 percent curcumin. After eight weeks take blood samples, sacrifice the bunnies and examine their aortas for atherosclerotic deposits. That’s a typical animal experiment to test the potential of curcumin — the compound responsible for turmeric’s yellow colour — in terms of its effects on reducing the risk of heart disease.
Turmeric is the ground up root of an East Indian plant, Curcuma longa, belonging to the ginger family. It has a long history of use in Ayurvedic medicine, based mostly on anecdote. Nevertheless it merits further investigation given that a number of drugs used in conventional medicine, digitalis being a classic example, came to the attention of researchers through anecdotal reports of efficacy.
In the case of curcumin, researchers found that the rabbits with the compound-supplemented diets had reduced blood cholesterol and less atherosclerotic deposits in their aortas. Does that mean people should start taking curcumin to ward off heart disease? Hardly. People are not rabbits. However, there is evidence from laboratory studies for curcumin slowing the multiplication of cancer cells as well as having anti-inflammatory properties.
The human body is not a large test tube and effects seen in the lab are rarely reproduced in the chemically complex environment of the human body. Still, the animal studies and the lab experiments suggest that curcumin supplements are reasonable candidates for investigation through human trials. Researchers, though, have not been able to pull a rabbit out of the hat. There is no magic in curcumin, at least as far as conventional science is concerned.
On the other hand, alternative or holistic practitioners don’t mind making claims of magic. These include the suggestion that intravenous curcumin solutions can effectively treat complaints ranging from eczema to low platelet counts. There is no evidence in the published literature for the use of intravenous curcumin for any condition. There are, however, examples of its use resulting in tragic consequences.
This past March, a young lady suffering from eczema visited a naturopathic doctor in California who had advertised the use of intravenous curcumin for inflammatory and autoimmune conditions. The first IV infusion resulted in cardiac arrest. Attempts at resuscitation failed.
The death was not readily explained because curcumin is not particularly toxic. Neither is it particularly soluble in water, which presents a problem for intravenous administration. Such an insolubility issue is commonly addressed with the addition of an emulsifier, a chemical that features a water-soluble region and a fat-soluble region in its molecular structure. The result is the production of a homogeneous solution.
In this case, a “compounding pharmacist” who used polyethylene glycol 40 castor oil as the emulsifier prepared the intravenous solution. This substance is used in the preparation of a variety of conventional intravenous medications that come with a warning of possible hypersensitivity reactions. Moreover, if this emulsifier is not properly purified it can be contaminated with diethylene glycol that is a byproduct of its synthesis. This too can trigger serious reactions. It seems the compounding pharmacist did not use pharmaceutical-grade emulsifier and it isn’t clear whether the lethal reaction was triggered by the emulsifier itself or some contaminant. There were no warnings on the label about possible hypersensitivity reactions. Another point of interest is that when the contents of the intravenous bag were tested by US Food and Drug Administration scientists, they found the curcumin concentration to be much lower than that declared on the label.
This tragic case highlights the fact that alternative practitioners sometimes use treatments that have no evidence of efficacy. Intravenous curcumin is one. Besides lack of proven efficacy, there is also concern that the products used are not subjected to the same type of rigorous quality control as conventional pharmaceutical products and may harbour various contaminants. Naturopaths would do well to remember the prime maxim of medicine, “first, do no harm.”
Joe Schwarcz is the director of McGill University’s Office for Science and Society. Read his blog at www.mcgill.ca/oss.