Hemp and marijuana are closely related. The recent explosion of interest in legalizing marijuana has indirectly shoved hemp into the spotlight. Several US states were already growing hemp despite DEA objections but in mid December of 2018 hemp production was legalized federally by the Hemp Farming Act provision of the 2018 Farm Bill. Many people have heard about at least one hemp product and been confused by the difference between hemp and marijuana.
Hemp and marijuana are different varieties of the same plant, Cannabis sativa, which have very different profiles of active chemicals
Hemp grows much faster and taller than marijuana. For thousands of years it has been used as a source of fiber for fabrics and paper, more recently as a biofuel and insulation. Hemp has also been used as farm animal fodder. The major difference of interest between hemp and marijuana is low to very low levels of the psychoactive chemical THC (tetrahydrocannabinol) in hemp.
Hemp contains high levels of another cannabinoid, CBD – cannabidiol. CBD doesn’t produce a “high” like THC, but has been studied for some other biological effects. These include treatment of epilepsy, anxiety, chronic and neuropathic pain and inflammation. Of these, only its effects in epilepsy have what is considered to be strong scientific support. There is also interest in CBD for controlling nausea and vomiting.
Despite the lack of good scientific evidence to support the use of CBD oil (there’s actually more for approaches that also use THC), it is widely available on the internet and being touted as a therapy for virtually any animal or human condition that has a component of inflammation, pain or anxiety which you can imagine is pretty much everything. Even colic is on the list, which is an irresponsible and potentially fatal suggestion. Unfortunately, these wildly indiscriminate claims are likely to inflame regulatory agencies and set back efforts to determine what the legitimate uses are.
Hemp seed oil is also being advertised as having the ideal omega-3:omega-6 ratio for horses. However, at 1:3 it is actually good for human but the inverse of what is appropriate for an equine diet. It also contains about 3% of the antiinflammatory omega-6 GLA, gamma linoleic acid. The 3% GLA does not compensate for the inverted omega-3:6 ratio or justify the high price.
It’s not uncommon to see articles discussing both hemp seed oil and CBD but there is no CBD present in the seeds. Further confusing things is products sold as “hemp oil” which are actually fat/oil soluble extracts of the whole plant, not the seeds.
Hemp seed meal, which is what is left of the seeds after the oil is extracted, is being sold as a protein supplement for horses. The residual fat is about 10%, protein 30%, which is similar to other cold-pressed seed meals. There is also a product called “hemp protein fiber” which is the screenings from meal production and is lower protein because of the hull fragments. Hemp protein has an OK amino acid ratio for horses but nothing to justify pricing over linseed or canola meal.
Finally, there are hemp beddings on the market which are apparently quite absorbent. Unfortunately they are also pretty palatable and impaction has occurred after eating them.
Hemp as a source of CBD may turn out to be very valuable but in the meantime beware of the marketing of superiority for all things hemp.
Eleanor Kellon, VMD
Dr. K's Horse Sense 