The Daily Woo: Glucosamine & Chondroitin
The Daily Woo is a brief summary of an alternative health treatment, as well as how it was experienced by me, Kate Donovan. I grew up with mostly alternative medicine (read: psuedoscience), and now you, lovely skeptics, get to live vicariously! (see note at the bottom of this post for an explanation of my attitude towards practitioners of pseudoscience.)
I have a bad knee. I’ve had it since I was in my early teens, the result of some bad ballet posture even before I hit the double digits. Every time my left knee bends, it gives the audio cues of popcorn in the microwave, and the knee-cap rattles around. I can’t kneel or sit cross-legged comfortably for more than a few minutes, and it’ll occasionally give way, much increasing my reputation for clumsiness. It’s not chronically painful any more, largely as a result of a sudden reduction in the number of hours spent in pink tights with my hair in a bun. This knee did, however, result in the some of my longest running anti-skepticism: glucosamine/chondroitin capsules.
Perhaps one of the most surprising parts of this story was that I was prescribed glucosamine by a medical doctor–a quite prominent sports doctor, who worked with our local basketball team. Ostensibly, it was going to better hydrate the cartilage in my knee, which would then respond by ceasing its movie-snack behavior. So, I took it faithfully, for years.
At some point after I had become a self-identified skeptic, I was wandering around the internet (read: procrastinating as hard as I could), and ran across a post by Greta Christina, Skepticism as a Discipline. It’s a lovely read, well worth your time, but one of the side notes Greta makes is an anecdote of her late application of skepticism to her use of glucosamine, also for a bad knee.
Obviously, this lead to furious googling on my part. Glucosamine is not cheap, costing upwards of twelve dollars a bottle–and the ‘all natural’ stuff can cost as much as twenty-five or thirty bucks for a month’s supply. That’s quite a bit of money to be spending on something that isn’t doing anything. But a doctor had prescribed it!
Turns out the dear old doctor was behind the times…. research that is just now becoming a matter of public knowledge.
Glucosamine/chondroitin is a supplement with a huge market, mainly in arthritis patients. A number of studies have occurred in the last decade, arriving at different conclusions about how successful it is in actually increasing water absorption in cartilage. The best designed studies showed no effect from supplement use, but there were more, lower-quality studies indicating a slight effect.
Further complicating things, studies done by the pharmaceutical companies appear to show the greatest effect size. Cue skeptical baby.
To the meta analyses!
A meta analysis is a study of studies–taking previous research and glomming it all together to examine overarching patterns. The Cochrane Musculoskeletal Group did a big one of these in 2005, and found that only a single brand (Rotta) of glucosamine seemed to do anything for arthritis patients. However, when they removed any old or poor-quality studies from the analysis, even that brand did no better than a placebo. Oddly enough, this research hasn’t made it out to the public yet, and though I was pleasantly surprised to see WebMD notes the apparent uselessness of this shellfish-derivative (referencing a more recent, but unavailable, meta analysis), it only does so after a long discussion of how it is used.
At 15+ dollars a month–at least–a little bit of exposure to research could save a good number of people, most of whom are elderly, a great deal of money. More recently, glucosamine has shown up in dog foods for the active or elderly animals. Of course, this comes with a price increase. Science–it saves you money!
Note: I am rather snarky in my dismissal of these practices. Alternative medicine does real physical and mental harm. It does not deserve kid gloves. People deserve respect, their bad ideas and the damage they do to others does not.
Featured image from here