Why it matters
The ECS modulates pain, mood, appetite, sleep, immune function, memory, and reward. CB1 receptors are concentrated in the central nervous system; CB2 receptors predominate in the periphery and immune tissue. Endocannabinoids are produced on demand and rapidly degraded, in contrast to the steady-state synthesis of most neurotransmitters.
In practice
For cannabis users, the relevant takeaway is that THC and CBD are recruiting an existing physiological system rather than acting on novel targets. That partly explains both the breadth of cannabis effects and the substantial individual variability.
Common confusion
The ECS is sometimes described as “discovered through cannabis.” More accurately, cannabinoids were the chemical probe that revealed an endogenous system that already existed.
This glossary entry is editorial content reviewed against primary sources. It is not medical advice. See our Editorial Policy.