The biggest difference between THC and CBD is their psychological effects on the brain.
THC is what gets a person high. CBD is not psychoactive. THC’s euphoric effects are a result of the cannabinoid binding to CB1 (cannabinoid 1) and CB2 (cannabinoid 2) receptors, predominantly located in the brain. This alters how the brain operates and is what causes the “high.” CBD doesn’t directly stimulate CB1 and CB2 receptors, but rather interacts with them indirectly.
Legal status is another major difference between THC and CBD. The laws surrounding marijuana and THC are typically strict. Currently, THC is federally illegal in the US, though it is becoming steadily legal on a state-by-state basis. Presently, the states that have legalized recreational marijuana include Colorado, Washington, Oregon, California, Nevada, Maine, Massachusetts, Vermont and Alaska. In addition, medical marijuana is legal in 29 states.
The legal status of pure CBD can sometimes be a bit fuzzy. The law is typically open to differing interpretations. For example, cannabis is considered a Schedule I drug, which means it is technically illegal under federal law. CBD is also found in hemp, which is legal and is used to produce a number of different commercial products sold throughout the US. In addition, the THC levels in CBD products also play a role in the legality surrounding CBD. As long as the CBD oil has less than 0.3% THC, it can be categorized as hemp under federal law making it legal to manufacture, distribute and purchase.