By Val Fan, Winter 2020.
In the East and West alike, traditional Chinese medicine (TCM) is often brushed off as a pseudoscience. Critics call it a placebo, and claim that its users are blinded by superstition. TCM boasts innumerable devoted followers in China, and not without reason. It dates back to ancient dynasties, drawing upon deeply rooted Chinese beliefs about harmony, energy, and the spirituality of nature. Such factors have compelled believers to, for example, imbibe tiger bone wine in the hope of absorbing the virility of the tiger. TCM includes herbal and animal-derived medicines, the latter of which is currently under fire from conservationists for the mass poaching of exotic animals with purported medicinal value.
Is there any truth to TCM practices, which may seem primitive or plain wrong from a Western perspective? To answer this question, I investigate some cases of animal use in TCM to see if they have any scientifically provable benefits.
For thousands of years, bear bile has been used in traditional Chinese medicine as a cure for liver and gallbladder disease. TCM practitioners maintain that the cool, bitter flavor of bear bile diffuses a “heat” concentrated in the liver, restoring bodily harmony. [1] Biochemistry provides a different explanation: the active ingredient in bear bile, ursodeoxycholic acid, works by protecting cholangiocytes (epithelial cells lining the bile duct) from cytotoxic bile acids; stimulating liver and bile secretions; and protecting liver cells against bile-acid-induced apoptosis (programmed cell death)— all of which help prevent and cure cholestatic disease. [2] For centuries, bears were killed for their bile, until in 1980, their critical endangerment led to the replacement of poaching with bear farms. Bear farms extract bile from live bears by implanting catheters or drilling fistulas (permanent holes) into their abdomens, which can have serious health implications for the bears. [3] Additionally, farmed bear bile is often contaminated with feces, urine, and bacteria.
So why not just use ursodeoxycholic acid (ursodiol)? TCM prefers the live substance over its chemical form; generally, people generally prefer bile from wild bears over that of farmed bears, and farmed bile over the ursodiol. [4] However, perhaps the issues regarding health and conservation can be remedied with another traditional belief that things with similar properties (i.e. flavor and appearance) can be substituted for each other, a belief that has gradually reduced the amount of endangered animal products sold on shelves by replacing them with those of less-threatened species. [1] Though no other mammal produces as much ursodiol as bears, research suggests that bile from different animals with similar bile salt contents can be used in place of bear bile.
Rhino horn is another staple of TCM believed to have “cooling” properties, and is used to treat ailments ranging from fever to gout. In 2008, demand for rhino horn in Vietnam skyrocketed after rumors circulated that it had cured a retired politician of cancer. [5] Rhinos have since been hunted to near-extinction for their horns, which are coveted not only as medicines but also as status symbols among Vietnamese nouveau riche.
While most horned mammals’ horns are primarily bone with a thin coating of alpha-keratin, an acidic compound, the rhino’s horns are entirely composed of it. Some scientists speculate that this acidity may be beneficial because “many poisons are strongly alkaline (basic) and may have reacted chemically with the keratin,” [6] but this is unlikely for a few reasons. For one, there are two types of alpha-keratin, one basic and the other acidic. Though currently no research is available regarding whether one type predominates in rhino horn, the ratio is likely approximately equal, because one of each type is needed to synthesize the alpha-keratin subunit dimer. [7] Therefore, the net acidity of alpha-keratin is likely not great enough to neutralize basic toxins. Rhino horn pills also contain such a small dosage of horn that, regardless of acidity, such pills would have negligible effect on curing a poison. Lastly, though some dietitians claim keratin can be taken as a supplement, the benefits of consuming keratin (the same material that comprises hair and nails) are not backed by research.
Though a fitting term for such remedies as rhino horn and tiger bone might be “snake oil,” ironically, some studies have revealed that snake oil may have actual health benefits. Oil from the Chinese water-snake is richer in eicosapentaenoic acid, an omega-3 fatty acid, than even salmon: eicosapentaenoic acid comprises 20% of snake oil, compared to 18% of salmon oil. [8] Omega-3 fatty acids are necessary for the normal growth and development of children, and must be obtained from diet because we as humans lack the means to synthesize them on our own. While omega-3 fatty acids are undoubtedly important, much confusion exists regarding their usage: in TCM, they are used not as dietary supplements for children, but as topical arthritis treatments. Western societies are also guilty of stretching the truth— omega-3 fatty acids, like apple cider vinegar and so many other treatments promoted on television and nutrition magazines, are purported to have additional benefits that include lowering the risk of cancer and heart disease. While it is certainly possible that omega-3 fatty acids could marginally ameliorate these conditions, so far, studies have shown a weak connection at best. [9]
Perhaps TCM is not as incompatible with modern Western medicine as it may seem. Though many animal remedies in TCM are ineffective or even detrimental, some have real benefits that are supported by scientific evidence. In addition, concerns about conservation can be addressed by substituting endangered animals with non-threatened species and by increasing awareness of the dire conservationist situation. Taking these factors into account, while also considering the surprisingly similar psychology behind certain treatments in TCM and Western culture, it may actually be possible to reconcile Eastern with Western medicine.
[1] Li, Sha et al. 2016. “Substitutes for Bear Bile for the Treatment of Liver Diseases: Research Progress and Future Perspective.” Hindawi 2016: 1-10. https://doi.org/10.1155/2016/4305074
[2] Paumgartner, G. et al. 2002. “Ursodeoxycholic acid in cholestatic liver disease: mechanisms of action and therapeutic use revisited.” J. Hepatol. 36, no. 3 (September): 525-531. 10.1053/jhep.2002.36088
[3] Loeffler, I.K., et al. 2009. “Compromised health and welfare of bears farmed for bile in China.” Anim. Welfare 18, no. 11 (August): 225-235.
[4] Dutton, Adam J., et al. 2011. “A Stated Preference Investigation into the Chinese Demand for Farmed vs. Wild Bear Bile.” PLoS One 6, no. 7 (July). 10.1371/journal.pone.0021243
[5] Ong, Sandy. 2017. “The Rich Men Who Drink Rhino Horns.” The Atlantic (June).
[6] PBS Nature. 2010. “Rhino Horn Use: Fact vs. Fiction.” https://www.pbs.org/wnet/nature/rhinoceros-rhino-horn-use-fact-vs-fiction/1178/
[7] Wang, Bin et al. 2015. “Keratin: Structure, mechanical properties, occurrence in biological organisms, and efforts at bioinspiration.” Progress in Materials Science 76: 229-318. http://dx.doi.org/10.1016/j.pmatsci.2015.06.001
[8] Kunin, R. A. 1989. “Snake Oil.” West J Med. 151, no. 2 (August): 208.
[9] Rizos, Evangelos C., et al. 2012. “Association Between Omega-3 Fatty Acid Supplementation and Risk of Major Cardiovascular Disease Events.” JAMA 308, no. 10: 1024–1033. doi:10.1001/2012.jama.11374