Some individuals have been found to have mutations on the CNR1 gene, which is responsible for coding the CB1 receptor (a type of receptor in cells throughout your body that interacts with cannabinoids). Issues with the CNR1 gene can ultimately result in a poorly functioning endocannabinoid system, which is an important variable when figuring out how to use CBD oil.
CBD oil contains CBD (and often other active compounds) in a carrier oil. There are a number of forms of CBD oil, including softgel capsules, tinctures, and under-the-tongue sprays. Some forms of CBD oil can also be applied directly to the skin, in the form of products like creams and salves. The concentration of CBD varies from product to product.