Steve Levitt, co-author of Freakonomics, has done me the great favor of bringing my omega-3 self-experimentation to a wider audience in this post. He thinks my results might be due to my expectations. I posted this comment:
Thanks, Steve, for writing about this. Here’s why I think the balance improvements I’ve noticed are unlikely to be due to expectations:
1. I first noticed the effect putting on my shoes the morning after I started taking flaxseed oil. I had been putting on my shoes standing up for two years; until that morning, I had always had trouble. Every morning. (I had expected it to get much easier — practice effect — but it didn’t.) The sudden improvement was a complete surprise. I had never heard of such an effect. I had hoped that flaxseed oil would improve my sleep.
2. The sudden improvement I saw when I switched from 2 tablespoons/day to 3 tablespoons/day was also a surprise, although I realize this may be harder to believe.
3. When I switched from flaxseed oil and walnut oil to sesame oil, I expected my balance to get worse. It did, but not when I expected. (It took 2 days to see a change; I expected to see it on the first day.)
Which is not to say I’m sure. If the effects I’ve seen are repeatable, I’ll test myself not knowing what oil I’ve ingested.
And forgot to sign my name. Oops.
My reading of the data (such as this ) is that placebo effects sometimes exist but are vastly overrated — like many dangers.
Addendum: Stephen Dubner, Levitt’s co-author, blogged today that
nearly everything we’ve written about, either in the book or our journalism or the blog, has some element of people worrying too much about something