Personal Science Week - 230928
An update on cancer diagnostics, plus links worth your time
Personal scientists try to be as open-minded as possible, taking seriously all ideas including those that others dismiss as wrong or inappropriate.
This week we find a counter-argument to our previous warnings about cancer diagnostics and point to a paper by an ethicist who thinks you’re not smart enough to make up your own mind
More on Cancer Screening
Last week we discussed the evidence that common cancer screening diagnostics appear to have little or no effect on what really matters: all-cause mortality. It does no good to screen for something, undergo treatment, and then die at the same rates as if you’d left it alone.
Well now we’ve heard a good counter-argument worth considering. In an Econtalk Podcast interview, Peter Attia offers the thought experiment of what would happen if you underwent a colonoscopy every three or four months. However unpleasant this might be, you would never die of colon cancer, since by design these procedures eliminate all potential problems. Even accounting for some of the inherent dangers in the operation, some simple math shows overall lives would be saved. Dr. Attia explains why he personally chooses to get a colonoscopy every three to four years:
I think Vinay [Prasad, the UCSF oncologist who argues against blanket testing] and [Peter Attia] come at this through totally different lenses, and neither is right and neither is wrong. Right? Vinay is coming at this through the lens of policy. He's coming at this through the lens of: What is the recommendation to all?
I'm coming at this through the lens of the individual. I'm giving you, as a person, a way to think about this for your decision around colon cancer.
In other words, follow the personal science. If you’re comfortable with the risks and you really understand the tradeoffs, then go ahead and test.
The Horror of Information in the Wrong Hands
A new paper published by a medical ethics group at U-Penn begins ominously:
Direct-to-consumer (DTC) laboratory tests are increasingly available to consumers with minimal or no involvement from health care professionals
The authors are concerned about “ethical issues, including appropriateness of testing, fragmentation of care, company liability, privacy of health information, and potential lack of follow-up for abnormal results”
But what if we rewrote the paper, substituting one word:
Medical textbooks are increasingly available to consumers with minimal or no involvement from health care professionals
Wouldn’t the exact same ethical issues apply?
You can appreciate the arguments for limiting powerful drugs to people who’ve been properly trained, but seriously, if you believe that DTC tests should be similarly limited, shouldn’t you want restrictions on all kinds of information, including — especially — medical textbooks?
Personal Scientist of the Week
Geekologist is a Seattle-based geek who made a 10-minute video analysis of the accuracy of a hundred cheap Casio digital watches that have been sealed in an art display for 10+ years.
Quartz watches are specked to drift about 30 seconds per month. By comparing the current displayed time, Geekologist was able to plot how much the watches actually moved over time.
Interestingly, the watches seem to drift in the same direction, but what accounts for the differences? Geekologist isn’t sure, but thinks it may have to do with how often the the factory recalibrates the machine that stamps out the watch components.
You’ll enjoy the video, which is quick and to-the-point. A good reminder that personal science is about more than just self-tracking or health-related inquiry.
Links Worth Your Time
I like the short, to-the-point style of Adam Rinde’s One Thing podcast. In this episode, Dr. Rinde interviews metabolism expert Ronesh Sinha, who specializes in South Asian health. Indians are on the whole, less active than other groups, he says, which explains their high rates of diabetes. Instead of trying to go on a full-blown special diet – which brings on issues of compliance – he suggests slight changes that are workable in the long run. For example, try to eat more protein.
Medications containing phenylephrine (i.e. most over-the-counter cold medicines) are completely useless, admits the FDA now after two decades. We know now, thanks to two Florida physicians, as The Atlantic’s Sarah Zhang explains. The common cough drugs guaifenesin and dextromethorphan are probably junk as well.
Beware the man of one study: Slate Star Codex on why you should be skeptical of a single study. Examples from drugs to treat depression, showing the range of positive and negative outcomes of the different studies. Then minimum wage research, where because the situation is confounded with politics, there’s even less uniformity of results. Also see Jason Crawford What does it mean to “trust science”? Science asks you not to trust, but to think
About Personal Science
Personal Science is the rigorous application of scientific techniques toward personal questions. We’re skeptical but open-minded about all claims we read in the news, and prefer whenever possible to test things ourselves.
Our weekly newsletter is free to everyone. Paid subscribers have access to our “Unpopular Science” series, including our recent one on the early 20th century scientific consensus on eugenics.
For interactive discussions with other Personal Science-minded people (including me), please join the Open Humans Weekly Self-Research Call, every Thursday at 10am Pacific Time. Open to everyone, and very friendly. (See Personal Science Week - 15 Sep 2022).
If there are other topics you’d like to discuss, please let us know.