Hemp crops are tall, have thick foliage, and can be planted densely, and thus can be grown as a smother crop to kill tough weeds. Using hemp this way can help farmers avoid the use of herbicides, gain organic certification, and gain the benefits of crop rotation. However, due to the plant's rapid and dense growth characteristics, some jurisdictions consider hemp a prohibited and noxious weed, much like Scotch Broom.
Most human studies of CBD have been done on people who have seizures, and the FDA recently approved the first CBD-based drug, Epidiolex, for rare forms of epilepsy. Clinical trials for other conditions are promising, but tiny. In one Brazilian study published in 2011 of people with generalized social anxiety disorder, for example, taking a 600-mg dose of CBD (higher than a typical dose from a tincture) lessened discomfort more than a placebo, but only a dozen people were given the pill.
There are hundreds of compounds in marijuana, but scientists believe the one responsible for the drugs' psychoactive effects is tetrahydrocannbinol, or THC. THC binds to cannabinoid receptors throughout the body, and marijuana's "high" comes from THC's binding to brain regions responsible for pleasure, time perception and pain, according to the National Institute on Drug Abuse (NIDA).
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