According to the National Institute on Aging, Alzheimer’s disease is an illness of the brain. It causes large numbers of brain’s nerve cells to die, which makes it harder to remember things and think clearly. It usually begins after age 60 and nearly half of people age 85 and older may have Alzheimer’s. An estimated 26.6 million people worldwide have Alzheimer’s as of 2006. This number may quadruple by 2050.
Unfortunately, doctors don’t know what causes the disease but have determined it’s not a normal part of aging. They have discovered that there is an increase in abnormal structures called plaques and tangles in the brains of people with Alzheimer’s. The plaques build up between nerve cells and contain deposits of a protein fragment called beta-amyloid. The tangles are twisted fibers of another protein called tau, which form inside dying cells. The plaques and tangles begin forming in areas important in learning and memory and then spreading to other regions. They have also found that levels of acetylcholine are abnormally low in the brains of Alzheimer’s patients. This is a neurotransmitter required for proper nerve function.
Alzheimer’s Disease and Cannabis
NOTE FOR FIRST TIME READERS: Cannabinoids – such as THC, CBD – and terpenes are the main medically active components in cannabis (aka marijuana). For more information on these components and much more about the plant, see our section on the Science of Cannabis.
Research has shown that cannabinoids work as an antioxidant and helps protect nerve cells from long-term damage or degeneration. There have also been several studies in recent years looking at their effect on Alzheimer’s. The findings show that cannabinoids may slow the progression of the disease. In addition, one of the cannabinoids in marijuana, THC, has been shown to help appetite and weight gain in Alzheimer’s patients with anorexia.
In a study by scientists at Scripps Institute, they have found that THC slows the formation of amyloid plaque, which is the main indicator (or marker) for Alzheimer’s disease. In fact, the study said that THC is “a considerably superior inhibitor of [amyloid plaque] aggregation” as compared to other drugs used for treating the disease. THC affects the enzyme (acetylcholinesterase) that causes the formation of amyloid plaque in the brains of Alzheimer patients. While generally very pleasant, THC-rich cannabis can be disorienting because of its psychoactive properties. That’s why it should be used with caution in people suffering Alzheimer’s Disease. CBD-rich strains (more info in Science of Cannabis) of marijuana are often mixed with THC-rich cannabis to reduce psychoactive properties.
Another study by researchers in Spain compared brain tissue from people who had Alzheimer’s before they died with brains from those of similar age who didn’t have the disease. They found that cannabinoid receptors in diseased brain tissue had dramatically lost their protective effect. Because cannabinoids offer both anti-inflammatory and nerve protection benefits, they concluded that cannabis could very well be a powerful therapeutic treatment for this devastating disease. No clinical trials with humans have been published for the study of cannabis and AD, so we don’t know dosage guidelines for this condition. CBD is successfully used to decrease agitation in AD and other dementia patients, and to treat “Sundowners syndrome”.
To treat this condition, you should choose the type of cannabis based on the specific benefits it offers. For Alzheimer’s, both CBD and THC are effective because of their antioxidant, nerve-protective properties. Using a combination or a specially developed hybrid can lower the psychoactive effects. For calming anxiety or to treat Sundowners syndrome, CBD is preferred.
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