Optimal cognitive function depends on efficient cellular energy production within neurons. The brain consumes approximately 20% of the body's total energy despite representing only 2% of body weight. When cellular NAD+ levels decline by 50% or more between ages 40 and 60, neuronal mitochondria cannot maintain the ATP production necessary for optimal neurotransmitter synthesis and signal transmission.
This energy depletion cascades into reduced acetylcholine availability—the primary neurotransmitter for memory formation and attention. When acetylcholine synthesis falls below optimal levels, the hippocampus struggles to encode new memories, while the prefrontal cortex experiences difficulty with executive functions like planning, decision-making, and sustained attention.
Chronic inflammation compounds these energy deficits by activating microglial cells that release inflammatory cytokines. These signaling molecules disrupt the blood-brain barrier, interfere with synaptic plasticity, and create the subjective sensation of mental cloudiness patients describe as brain fog.
