@hansw@mastodon.social THC is THC, and CBD is CBD, they are no different from one strain to the next.

The reason different strains give different effects is because of the ratio of the canibinoids, specifically the ratio of CBD to THC which is the vast majority of what determines effect.

"head highs" as they are called are plants high in THC and low in CBD, sometimes as low as 0.1%. Body highs or mellow highs (where you want to fall asleep) would be the result of a high CBD content along side a decent amount of THC, a 1:1 ratio of each would give an effect that would make you feel tired and relaxed without much of a head high at all.

CBD only has a psychological effect when along side THC though. While CBD's psychoactive effect is very significant along side THC it has almost no psychoactive properties when on its own. The reason for this is how it acts on the receptors in your brain. THC by itself is whats called an Agonist for CB1 and CB2 receptors. By itself it will equally bind and "activate" these two receptors, thus causing the head high. On the other hand CBD is what is called a Antagonist of CB1 and CB2 receptors, though has a more significant effect on CB1 than it does on CB2, what this means is it **blocks** the effect of THC such that the THC has less of an effect and the diminished effect is more pronounced with its binding on CB1 than on CB2, this means when CBD is present along side THC not only is the overall effect significantly diminished but the binding of THC to the receptors is no longer balanced between CB1 and CB2 and almost all the activation occurs on the CB2 receptors. This is why CBD will alter the effects of THC but not have any effects on its own.

All that said it means when you have an isolation of nearly pure THC with no CBD present not only will you get a head high, but the severity of the high will be significant (so usually a good idea to do a much lower dose.