CBD works by interacting with the body’s endocannabinoid system (ECS), a complex system of receptors and neurotransmitters that regulate a variety of bodily functions such as mood, pain, sleep, and immune response. The ECS is made up of two main types of receptors: CB1 receptors, which are primarily found in the brain, and CB2 receptors, which are found in the immune system and other peripheral organs.