Although the brain represents only 2% of total body weight, it contains 20% of the body’s cholesterol. What is all that cholesterol doing up there?
Synapses— the magical areas where communication between brain cells takes place—are lined by cholesterol-rich membranes responsible for passing neurotransmitters like serotonin, GABA, and dopamine back and forth.
Myelin, the white matter that insulates brain circuits, is made from tightly-wound membranes containing 75% of the brain’s cholesterol.
Cholesterol also helps guide developing nerve endings to their destinations on “lipid rafts”. If the brain is too low in cholesterol, its membranes, synapses, myelin and lipid rafts can’t form or function properly, bringing all brain activity—including mood regulation, learning, and memory— to a screeching halt.