Called FTL1. In aging mice, higher levels of this protein weakened connections between brain cells and caused memory decline. Reducing it reversed some of that.

Mice aren’t humans. But every time something like this shows up, it’s one more piece of the puzzle of why the brain degrades. The idea that aging might be modifiable rather than fixed is no longer fringe science.

Filed under: things I hope pan out before I need them.

16-year study. ~800 people. Higher Vitamin D levels in midlife → lower tau protein levels later. Tau buildup is associated with Alzheimer’s and other forms of cognitive decline.

The implication is that the decisions you make in your 30s and 40s are already shaping what your brain looks like at 60 and 70.

Vitamin D is cheap. Sunlight is free. The study design isn’t perfect but it’s hard to argue against checking your levels.