Date: October 4th, 2025 12:53 PM
Author: powerfully online
This is a mix of truth, speculation, and pseudo-anthropology. It’s a kind of “folk evolutionary psychology” explanation, and while some pieces touch on real biology, the sweeping claims about “Nordoids” or “metabolism evolved for weak tonics” aren’t supported by hard evidence. Let’s break it down:
1. Light, Vitamin D, and Seasonal Depression
True part: People at northern latitudes (Scandinavia, Canada, etc.) get less sunlight, especially in winter. This increases risk for vitamin D deficiency and can exacerbate Seasonal Affective Disorder (SAD) — which is real, well-documented, and does respond to vitamin D and light therapy.
But: Not every “Nordic” person has the same vulnerability, and the mechanisms are more about current vitamin D and circadian rhythms than about some uniquely “light-linked neurochemical balance” evolved over millennia.
2. Caffeine, Dopamine, and Adenosine
True part: Caffeine does block adenosine receptors, which indirectly affects dopamine and alertness. Some people are much more sensitive to caffeine due to genetic variants (especially in the CYP1A2 gene, which controls how fast you metabolize caffeine).
But: Sensitivity to caffeine is not neatly tied to ethnicity. Within any population (Nordic, East African, East Asian, etc.), you’ll find both “slow metabolizers” and “fast metabolizers.” This is a gene-level difference, not a “culture-level” one.
3. Coffee vs. Traditional Stimulants
True part: Coffee originated in Ethiopia and Yemen. Khat (a stimulant plant) has indeed been chewed in East Africa and the Arabian Peninsula for centuries. Nordic peoples did use mild herbal teas (pine needles, birch bark, etc.), but those don’t have caffeine-like alkaloids.
But: There’s no evidence that Ethiopians or Yemenis evolved a “tolerance” to caffeine or other alkaloids over millennia. Tolerance to stimulants is not typically an inherited adaptation on a population scale—it’s something individuals build in days to weeks of use, and genetic changes of that kind take tens of thousands of years and very strong selection pressure.
4. “Nordoid metabolism became hypersensitive”
This is folk theory. There’s no evidence that northern Europeans have a uniquely hypersensitive metabolism to stimulants because of historical beverage choices.
What is real:
Populations differ in CYP1A2 variants (caffeine metabolism) and ADORA2A variants (caffeine sensitivity).
Northern Europeans don’t show especially high rates of slow caffeine metabolism compared to other groups.
Individual variation matters more than ancestral beverage culture.
5. Bottom Line
The seasonal depression/vitamin D link = real.
Caffeine affecting people differently = real, but mostly genetic, not cultural.
“Nordic brains evolved for weak tonics” = storytelling, not science.
This is a good example of how real phenomena (SAD, caffeine genetics, traditional beverages) can get blended into a neat “ancestral narrative” that sounds plausible but isn’t supported by actual evidence
(http://www.autoadmit.com/thread.php?thread_id=5782329&forum_id=2\u0026show=month#49324643)