Cannabis Works Through a System Your Body Already Has

The Fact

1. Your body has its own cannabinoid system. It's called the endocannabinoid system (ECS): a signaling network that runs through the whole body. The two main receptors are CB1, found mostly in the brain and nerves, and CB2, found mostly in the immune system and other tissues. The system helps regulate pain, appetite, nerve signaling, metabolism and immune function.
2. Your body makes its own cannabinoids. The two best studied are anandamide and 2-AG. The body makes them on demand when a signal is needed, instead of storing them like a hormone.
3. THC works by plugging into receptors your body already uses. THC, the main ingredient in cannabis that gets people high, acts mostly on CB1 receptors. Those receptors didn't evolve for marijuana; they are there for the cannabinoids the body makes itself.
4. Some medical uses are established. The National Academies' review found strong evidence for three uses: chronic pain in adults, chemotherapy nausea and vomiting (oral cannabinoids), and muscle stiffness from multiple sclerosis (oral cannabinoids). It found moderate evidence for short-term sleep improvement.
5. It kills some bacteria in the lab. In lab and animal studies, CBD and CBG killed some bacteria, including MRSA and strep. Human trials have not been done yet.
6. It attacks cancer cells in the lab. In cell and animal studies, cannabinoids triggered cancer-cell death, slowed cancer-cell growth and cut off tumors' blood supply. The National Cancer Institute and ASCO say the evidence in people is not there yet to use it as a cancer treatment; its proven role in cancer care is easing nausea from chemo.