Should People Avoid Whole-Body Screening Info?

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Should People Avoid Whole-Body Screening Info?<br>...

Scott Alexander<br>Jun 23, 2026

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The most controversial part of last week’s article on the Midjourney ultrasound scanner was medical experts’ recommendation against whole-body screening (including existing whole-body screening technology using MRI).<br>Isn’t this crazy? Whole-body screening can save lives by detecting serious diseases like cancer. The experts counterargue that it finds so many false positives - minor zit-like imperfections that would never have caused problems, but which cost patients time, money, anxiety, and side effect burden to investigate - that it ends up net negative. But isn’t this just a problem of setting thresholds correctly? Can’t you commit to only investigating the most obviously bad things, then ignore the rest?

Joshua Achiam@jachiam0

Seeing reactions like "Frequent scanning is bad, over-testing leads to unnecessary procedures that cost thousands of dollars." This take is catastrophically wrong. More data is unequivocally good. We should adjust the threshold for follow-on procedures, not make ourselves blind.

Midjourney @midjourney

Announcing a new division of Midjourney called "Midjourney Medical"

10:43 PM · Jun 18, 2026 · 152K Views

73 Replies · 44 Reposts · 1.02K Likes

Amanda Askell@AmandaAskell

The view that we shouldn't do more medical scans because incidental findings cause a lot of harm doesn't sit well with me. It seems like the issue it points to isn't the scan but the response to it. If you see something on a scan but have no other symptoms, you could ignore it.<br>2:41 AM · Jun 20, 2026 · 171K Views

165 Replies · 48 Reposts · 1.79K Likes

mattparlmer 🪐 🌷@mattparlmer

Harvard trained physician wants you to skip prophylactic scans lmao

This shit is beyond parody

Jason Ryan @jasonryanmd

Whole body scans in asymptomatic people won't save lives overall. They will mostly find benign incidentalomas that cause anxiety for otherwise healthy people. Many of us have benign growths that mimic cancer but are harmless. These will be discovered leading to unnecessary panic

1:20 AM · Jun 19, 2026 · 84.3K Views

66 Replies · 8 Reposts · 350 Likes

@AmandaAskell They're basically saying that their system is so bad it has decided the best solution is to stick their heads in the sand and that if we don't do the same, we're somehow anti science.","username":"LoganFizzle","name":"Logan Fizzle","profile_image_url":"https://pbs.substack.com/profile_images/2028674817780752384/d7IzGGzv_normal.jpg","date":"2026-06-21T17:27:45.000Z","photos":[],"quoted_tweet":{},"reply_count":0,"retweet_count":0,"like_count":0,"impression_count":388,"expanded_url":null,"video_url":null,"belowTheFold":false}" class="pencraft pc-display-flex pc-flexDirection-column pc-gap-12 pc-padding-16 pc-reset bg-primary-zk6FDl outline-detail-vcQLyr pc-borderRadius-md sizing-border-box-DggLA4 pressable-lg-kV7yq8 font-text-qe4AeH tweet-fWkQfo twitter-embed">

Logan Fizzle@LoganFizzle

@AmandaAskell They're basically saying that their system is so bad it has decided the best solution is to stick their heads in the sand and that if we don't do the same, we're somehow anti science.<br>5:27 PM · Jun 21, 2026 · 388 Views

This seemed like an interesting problem to investigate in more depth, so I’ve tried to get numbers. These are rough estimates loosely based on parameters extracted from unsatisfactory studies1 - please don’t take them seriously as exact values, just as right-order-of-magnitude estimates. We’ll focus on whole-body MRIs, since this is a well-studied existing technology, then speculate later on how the results might generalize to whole-body ultrasound.<br>For every 1,000 seemingly-healthy people who get whole-body screening MRIs:<br>680 look fine and no follow-up is needed.

300 have mildly concerning findings. They’re told to follow-up with specialists, get further tests, or come back for more imaging later.

20 have extremely concerning findings and get immediate biopsies (surgeries to collect tissue samples from the area).

Of those 20 people who got biopsies, 10 turn out to really have some serious disease. This is usually cancer, and for simplicity we’ll focus entirely on cancer going forward.

Of those 10 cancer patients, 4 end up living longer and healthier lives because their cancer was detected early. The other six either have such slow-growing cancers that they would never have noticed before dying of something else, or such deadly cancers that detecting them early doesn’t help, or would have been found by standard screening so soon afterward that the extra screening didn’t buy meaningfully more time.

Meanwhile, the 300 people who followed up with specialists and got extra tests will spend some number of years seeing more doctors and getting more tests and waiting and seeing, and eventually for 4 of them this will result in detecting some dangerous...