In einer Studie mit 2.044 Erwachsenen über 64 Jahren wurden höhere Vitamin-C-Spiegel mit einem größeren Volumen der grauen Substanz und einer stärkeren Netzwerkkonnektivität im Standardmodus (die mit Aufmerksamkeit und autobiografischem Gedächtnis verbunden ist) in Verbindung gebracht, was auf eine mögliche Rolle bei der Erhaltung der kognitiven Funktion während des Alterns hindeutet

>“Our study demonstrates that higher plasma vitamin C levels are associated with better preserved structural connectivity of the default mode network (DMN), a key brain network involved in cognitive function. This finding generates the exciting hypothesis that a diet rich in vitamin C might play a supportive role in maintaining brain health and mitigating age-related cognitive decline in older adults,” Dr Tomohiro Shintaku at Hirosaki University, Japan said.
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>“It truly highlights the potential impact of our everyday dietary habits on our brain structures.”
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>For the study, published in the journal PLOS One, researchers at Hirosaki University, Japan analysed magnetic resonance imaging (MRI) scans and plasma vitamin C levels of 2,044 Japanese adults over the age of 64.
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>They measured each participant’s gray and white brain matter and evaluated connectivity in the default mode network, which is associated with attention and autobiographical memory.
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>After accounting for factors such as age, activity levels and education level, researchers found that participants with lower plasma vitamin C levels tended to have lower gray matter volume, as well as lower connectivity within the default mode network.
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>These findings suggest vitamin C could support cognitive function and counteract cognitive decline. But the findings only showed an association between vitamin C levels and brain health and not cause and effect.
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[Plasma vitamin C levels are associated with brain structural networks on MRI: A large cohort study | PLOS One](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0348504)

How does a diet with high vitamin c look like in the context of the study?

This is purely anecdotal, but I recently started supplementing vitamin C after I started having scurvy symptoms (I apparently have a vitamin C malabsorption issue that went undiagnosed and my diet is pretty poor, not poor enough to cause scurvy in a normal person but very much enough to do it in me), and aside from scurvy subsiding almost immediately, ADHD meds started working (I’ve been on methylphenidate for a moment and it did very little, now it helps me massively), I was able to retain information accurately while studying again to the point that I’ll be going back to college soon, and I’m reading a whole book a week again after not doing it since middle school

Edit: oh I forgot, my IQ had gone down by 22 points between 15 years old and 21, and I did feel a lot stupider

What in the world is grey matter

So Linus Pauling was into something after all.