"The worthlessness of vitamin D is mildly exaggerated" by dynomight cover art

"The worthlessness of vitamin D is mildly exaggerated" by dynomight

"The worthlessness of vitamin D is mildly exaggerated" by dynomight

Listen for free

View show details
For a while there, many people thought vitamin D was magical—that it could improve bones, the heart, infections, cancer, heart disease, longevity, even mental health. But among people I respect, opinion is now overwhelmingly that taking vitamin D does nothing unless you're severely deficient. The central argument is that while vitamin D levels are correlated with ~all positive health outcomes, when you actually test vitamin D supplements against placebo in randomized trials, nothing ever happens.

That's what I used to think, too. But I've come to think the skeptics have over-corrected. Yes, randomized trials have shown the magical correlations are not causal. But if you start with non-insane expectations, the trials look like weak but positive evidence. And if you consider what we know about biology and evolution, I think the balance of evidence tips pretty clearly in the direction that people with low-ish levels would be wise to supplement.

Am I certain that vitamin D is beneficial for people with low-ish levels? Absolutely not! But I claim that's the best bet given the limits of our knowledge.

The classical view: Boring bone vitamin

Most vitamins are "ingredients" that the body uses to do stuff. Vitamin D is more [...]

---

Outline:

(01:19) The classical view: Boring bone vitamin

[... 14 more sections]

---

First published:
June 23rd, 2026

Source:
https://www.lesswrong.com/posts/sF5gAxnmifQe2TBNt/the-worthlessness-of-vitamin-d-is-mildly-exaggerated

---



Narrated by TYPE III AUDIO.

---

Images from the article:

Apple Podcasts and Spotify do not show images in the episode description. Try Pocket Casts, or another podcast app.

adbl_web_anon_alc_button_suppression_t1
No reviews yet
In the spirit of reconciliation, Audible acknowledges the Traditional Custodians of country throughout Australia and their connections to land, sea and community. We pay our respect to their elders past and present and extend that respect to all Aboriginal and Torres Strait Islander peoples today.