illuminating science

I have a friend who, upon getting the first hints of a cold, goes on a strong diet of zinc, horseradish, garlic, vitamin C, echinacea, and other herbs as appropriate - all obtainable in convenient pill form. As a bit of a skeptic, I’m inclined to believe that a balanced diet will get you most of what you need and that, in general, this is a pretty good scam by the so-called “natural therapy” companies. (I don’t really see why people mistrust drug companies as the Root of All Evil (TM), and yet will happily hand over hundreds of dollars for completely unproven herbal remedies…let alone magnetic therapy!)

However, one particularly interesting herb is echinacea which is supposed to boost your immune system and either protect against the common cold or at least reduce your symptoms. While some people swear by it, I can’t help but attribute it to a combination of placebo effect and selective memory (”Wow, this cold wasn’t anywhere like as bad as my last one. Thanks echinacea!”) Studies have both supported and contradicted its healing powers, and I’ve previously seen lots of bad science on the “support” side. Hence, I’ve been skeptical, and pretty much put it in the money-money-money pile of “natural” remedies, pending further studies.

Cue Dr Craig Coleman, from the University of Conneticut doing a review of 14 earlier studies, involving 1600 people. He found that echinacea typically reduces your odds of catching a cold by 60%, and reduces the length of the colds you do catch by about one and a half days. Now that’s pretty good odds - half as many colds, and only 2-3 days off instead of 3-5! I’ll still maintain a little skepticism because, as Dr Coleman (a pharmacist) points out, for a really clear result, “someone needs to do a really large, well-done, randomised trial. That is unlikely to occur because there is a lack of funding.” Why? No-one can patent echinacea, so no-one will front up the money for a study like that! (Particuarly not if it turns out to do better than commercial meds! But that’s veering towards conspiracy theories…)

Interestingly, though, there’s a flip side - if echinacea really does stimulate the immune system, it could be harmful to people who already have overactive immune systems. People with autoimmune diseases, where the immune system attacks healthy cells, actually take immunosupressants which reduces the immune response. Dr Coleman also points out that although there are no harmful effects observed so far, there hasn’t been any long terms studies. Just because it’s natural, doesn’t mean it’s safe! (Hemlock, anyone? And again, people demand long term studies for drugs which might save their lives, but if a herb can stave off the cold then full steam ahead. I don’t get it.) Whether one should be taking it as a preventative then? In general, you want to do as little to your body as you can, I think, so I guess there’s a trade off there - unknown risks, vs cold prevention.

Either way, I am probably now swayed enough to purchase some echinacea, just for when I get a sniffle. Even if it shouldn’t, perhaps I’m now convinced enough for the placebo effect to kick in!