A phenomenon known as “the entourage effect” suggests that terpenes and cannabinoids like CBD and THC create a union of compounds that can achieve better results as a group than they would in isolation. Simply put, the entourage effect magnifies the therapeutic benefits of the plant’s individual components so that the medicinal impact of the whole plant is greater than the sum of its parts.
The levels of THC and CBD and the presence of certain terpenes influence what effects the strain will have on your mood and health. This might explain why people with certain medical conditions seem to benefit more from one strain over another with a similar THC level. For example, if you have 2 different types of cannabis and both have 15% THC, but one gives you energetic effects and one gives you sedative effects, this is largely due to the different terpene profiles.