Jane Brody has written about health for the New York Times for a long time. Recently, a blood test indicated that her total cholesterol was 222 and her LDL was 134, which she believed was too high.
Missed Opportunity #1: She had no idea of the error in these numbers. It would have been better to get a second measurement to get some idea of the error. What if the second measurement of total cholesterol was 180?
She made various non-drug changes. She stopped eating cheese and lost a few pounds. She believed this would lower her cholesterol. It didn’t. A new test found total cholesterol was 236 and LDL was 159.
Missed Opportunity #2: She still had no idea of the error in these numbers.
Missed Opportunity #3: If the change from 134 to 159 was not random error, it was possible that cheese was lowering her cholesterol — the opposite of what she believed. She failed to consider this possibility — at least, she doesn’t mention it.
She made more extreme changes:
Now it was time to further limit red meat (though I never ate it often and always lean), stick to low-fat ice cream, eat even more fish, increase my fiber intake and add fish oils to my growing list of supplements.
Her cholesterol numbers got even worse — total cholesterol was 248 and LDL 171.
Missed Opportunity #4: She still had no idea of the error in these numbers.
Missed Opportunity #5: She again failed to consider the possibility that what she was told was wrong — that things she did to lower her cholesterol actually raised it.
Her doctor tells her: “Your body is spewing out cholesterol and nothing you do to your diet is likely to stop it.”
Missed Opportunity #6: She failed to consider what this says about her doctor. If her doctor believes this, why didn’t he or she say so earlier?
Missed Opportunity #7: She failed to ask her doctor the basis for such an extraordinarily broad claim (“nothing you do”).
Missed Opportunity #8: She failed to realize her own data called this statement into question. Her own data suggests that diet made a difference (if the random error is small enough). She changed her diet, her cholestrol changed.
My own self-experimentation started with the discovery that some of what my dermatologist told me was wrong. A certain antibiotic was supposed to reduce my acne; if anything it increased my acne.
The classic case of a self-experimenter failing to learn something he could have learned is Barry Marshall, the Australian doctor who won a Nobel Prize for showing that bacteria cause ulcers. He drank a flask full of the bacteria — this was the self-experiment. Results: 1. He didn’t get an ulcer. 2. He became infected and the infection went away after treatment with a drug later found to have no effect against the bacteria. Warren might have concluded that some people can successfully fight off infection from the bacteria and that the people who get ulcers are not those who are exposed to the bacteria (which is probably almost everyone) but those who can’t fight it off. Warren’s self-experimental results, like Brody’s, supported a conclusion quite different from the conclusion he started with, and he failed to notice — or at least mention — this.