This graph shows recent results from the test I used to track my brain function. The test is a choice reaction task done on my laptop: see a digit (e.g.,”2″), press the corresponding key as fast as possible. The x axis shows the time of the test. The ticks (“Sat”, etc.) mark the beginning of the associated days. The y axis shows the average percentile of the reaction times. Higher percentile = faster. (Let me explain what “percentile” means: Each reaction time is compared to earlier reaction times with the same stimulus, and its percentile is computed. For example, a percentile of 60 means that 60% of previous responses were slower.) An average of 60 is quite good and 40 is quite bad. I usually do two tests per day, one right after the other, in the late afternoon (e.g., 4:30 pm).
On Friday and Saturday, my scores were close to normal. On Sunday afternoon, however, my scores were much worse than usual; the average score was about 15. A score that low might happen once per year. The next day (Monday) I tested more often than usual — both morning and afternoon — and my scores gradually returned to normal. On Tuesday I also tested both morning and afternoon. My scores were ordinary the whole time. This showed that the improvement Monday morning was not normal.
What happened Sunday? I am pretty sure the problem is my lunch at a middle-cost noodle restaurant whose English name is Flying Noodle. It is close to the Tsinghua campus but I’d only been there once before (and eaten almost nothing that time). On Sunday I had a small pickled vegetable dish and an ordinary-sized plate of fried eggs and tomatoes. I suspect the problem is the oil used to cook the egg and tomato. It might have been soybean, corn, sunflower or peanut oil, all high in omega-6. (There are also complaints about reuse of cooking oil.) As I entered the restaurant, I worried about the oil, but also thought who really knows? By the time of my brain test, I had forgotten my concern.
A friend was with me. She ate different dishes. She found that her scores on a iPhone game she often plays, which requires fast reactions, were suddenly and mysteriously worse after the lunch. Then, in about a day, they recovered.
This interests me in several ways:
1. New phenomenology. In this example and my earlier tofu results (a piece of fermented tofu reduced my brain score for two days), I noticed something never noticed before: Sharp changes (bad) in brain function. Fortunately I quickly recovered. Nobody knew this happened. It’s like looking through a microscope or telescope for the first time, but with much more relevance to everyday concerns.
2. Comparison with Super Size Me, a 2004 documentary by Morgan Spurlock, which argued that McDonald’s food was unhealthy. Spurlock ate only McDonald’s food for 30 days. Realism: Spurlock ate far more McDonald’s food than anyone would normally eat; I ate one meal. Information value: Spurlock’s test was so unrealistic and his diet so plainly unhealthy that I doubt the results — Spurlock’s health got worse, he gained weight — have any implications for the rest of us. In contrast, I find my results horrifying. Bias: Spurlock was obviously biased against McDonald’s before he started. I thought favorably of the Flying Noodle — that’s why I went there. Cost: My data cost essentially nothing, Spurlock’s movie cost $65,000, not to mention the damage to Spurlock’s health. Recovery time: Spurlock took 14 months to lose the weight he gained. I recovered in a day. Repeatability: My test is easy to repeat, Spurlock’s very difficult.
3. Public health disaster? China has a very high rate of diabetes, for unknown reasons. Chinese teenagers and college students have much worse (inflamed) skin than I see in other countries. Old people in China look much worse than old people in Japan. Could heavy use of high-omega-6 cooking oil be a big reason?
4. Where were authorities? We expect our government — in combination with academia — to protect us against dangerous chemicals in our environment. If I’m right about the cause of my low score, that didn’t happen here. Cooking oil is the opposite of a rare food. If ordinary amounts of a common cooking oil did cause these results, it suggests something is seriously wrong with the regulatory system. A big argument for personal science — and brain tracking in particular — is that you monitor exactly the environment to which you are exposed in exactly the genetic context you care about (yours).