CBD, THC and other cannabinoids are found in cannabis plants, concentrated most highly in the flowers of the unfertilized female plants. Hemp is a term used to designate cannabis plants that are non-psychoactive and have a low level of THC (usually designated as less than 0.3%THC) and most often used for fiber, food, fuel and building materials. THC, CBD and other cannabinoids are also found in the leaves, stems, roots and seeds of cannabis plants. There are special laws governing cannabis and hemp, and sometimes CBD and cannabinoids are only permitted to be extracted from the branches, stalks and seeds of the hemp plant, and not the flowers. For the best explanation of how the oil was obtained, check with the producer of the oil, to determine if the oil is derived from flowers, or stems, and to make sure that the extract is a "whole plant extract", as the synergy obtained from all of the cannabinoids and compounds in cannabis is far superior than any one cannabinoid in isolation.
At a molecular level, there is really no difference between either. Cannabidiol is cannabidiol – and it makes no difference if it comes from cannabis or hemp.
However, people report being affected differently based upon the source – that is, whether the CBD came from hemp or cannabis and, more specifically, they claim that the CBD from hemp just doesn’t seem as effective. This may be psychosomatic, or it may be because a little bit of THC can boost the effectiveness of CBD by a chemical reaction known as the entourage effect. An analogy would be in the making of bread, where you have the minimum of ingredients, flour, water, yeast, and salt – all are needed for the best effect. If you leave out the salt – even though the recipe calls for only a pinch – you end up with a very unappetizing dense loaf of wood. The salt is required for a specific chemical reaction that properly binds the other ingredients and causes an optimal reaction that results in a rising dough and ultimately a satisfying loaf. That’s an entourage effect. Many believe that for CBD to be truly effective it also needs small amounts of THC and, perhaps, other cannabinoids too. Unfortunately there has been little testing at scale to know one way or the other.
So, for now we can only go by anecdotal experience of others. And that’s my advice for now too – try it. Make sure all controllable conditions are equal. Try just CBD derived from Hemp on it’s own – and then try CBD derived from cannabis on it’s own
As Dr. Solomon points out in the video, CBD is CBD, but the issue of what else may or may not be present in ‘CBD oil’ is an important one to think about. To begin with, CBD oil derived from medical cannabis and sold as medicine seems less likely to contain industrial contaminants or impurities stemming from the commercial hemp operations from which non-medicinal CBD oil is sourced. There is generally a lot more scrutiny of medical cannabis products from field to consumer, which is obviously a good thing if you are the consumer. Dr. Solomon also makes the point that the biochemical context is known to be important in the way medical cannabis creates its effects. Because it has been so well demonstrated that cannabinoids interact in producing the effects we perceive, it seems important to remember that fact when we are attributing specific activities to a single isolated cannabinoid. In fact, the presence or absence of biologically active amounts of some of the many other cannabinoids in a particular CBD oil might account for some of the variability of patient experience with CBD oils in general.
Hemp-based CBD oil is low in THC or/and CBD) where cannabis plant-based CBD oil is rich in THC or/and CBD. Hemp oil, unlike cannabis oil has only trace amounts of THC and CBD, and therefore will be 100 times less potent than cannabis oil.
First, there is a slight misnomer in this question. Cannabis is the name for both "marijuana" (THC) producing and "industrial hemp" (THC < 0.3%). It is all in the genes as to what proportion of CBD:THC is produced. The other differences that could be realized would be in the mix of other cannabinoids and terpenes, along with the final percentages of both CBD and THC in the extracted oil. That also can all be tuned by the extraction process which can be fine tuned to pull out almost any specific component and then selectively add certain components back in. Always look for the actual amount of CBD (mg count or parts per million, PPM) to ensure what you are getting. Also know that if you don’t want THC, marijuana based oil will need to go through more refinement to remove/lower the THC content.