Great article re that: https://www.nature.com/articles/ncomms7342#affil-auth https://www.nature.com/articles/ncomms7342#affil-auth and choline (see above URL)

Great article re that: https://www.nature.com/articles/ncomms7342#affil-auth https://www.nature.com/articles/ncomms7342#affil-auth and choline (see above URL) matters for the brain: The Case for Choline The nutrient is essential for brain development and much more, but most Americans get nowhere near enough. By Hara Estroff Marano, published on January 3, 2017 - last reviewed on March 6, 2017 https://www.psychologytoday.com/articles/201701/the-case-choline?destination=node%2F1099765 https://www.psychologytoday.com/articles/201701/the-case-cho... BUT - the modern diet produces more cavities, the ancient diet more choline (better for brain development.) So more work is needed for this hypothesis than what I've cited above. The bug that causes cavities from sucrose exposure (and you're right, there is a specific one) might have an IQ effect too. Certainly not impossible.