Higher homocysteine—a sign of low B12 and folate—was tied to more fatigue and lower motivation in healthy adults, hinting that diet may sap daily energy.  

In a small trial, melatonin boosted a DNA‑repair marker during daytime sleep in night‑shift workers, hinting at a broader repair role beyond sleep support.  

Sleep loss weakened a social‑memory circuit in the brain, but caffeine precisely restored this pathway, reversing memory problems in sleep‑deprived animals.  

When the brain becomes the bottleneck, healthspan shrinks even if labs look “normal.” A brain‑first lens puts neural resilience at the center of longevity.