Effects of Marijuana

by | Apr 22, 2013 | Blog, Mood/Neurotransmitters | 7 comments

There is so much controversy on the effects of marijuana. Some people say that it is a “natural” drug and therefore it is healthy. Other people say that there are some negative consequences of marijuana use. I wanted to write an article after doing research on the matter. The answer I found is Marijuana definitely has negative effects on the mind and body.


Marijuana and Brain Processing Speed

Myelination is the process by which brain cells, neurons, are coated with a protective sheath that increases the brain’s processing speed. Researchers showed, in a study which appeared in the Journal of Psychiatric Research, that heavy marijuana use among young adults and adolescents may affect normal brain development by interrupting the myelination process. This process isn’t completed until the age of 25 and it starts at the back of the brain and works its way forward. This explains why subjects in the study showed issues with their prefrontal cortex (PFC) and temporal lobes, the last areas to be coated. These areas are involved with decision making, attention, executive functioning, memory, and language. If these areas of the brain were not able to develop properly, it makes sense that one might have issues staying focused and making decisions.1

Marijuana and Brain Function

Marijuana can alter many brain functions. It can specifically alter serotonin and melatonin levels in the brain. Many people smoke it in the evenings to relax and get to sleep. It has been shown that one joint of marijuana can raise melatonin production up to 4,000%! No wonder why marijuana can knock people out or make them feel lethargic.2 Although marijuana may help people fall asleep, it has been shown to interrupt the later phases of REM sleep. REM sleep is very important in making the body feel well energized after waking. Marijuana, like alcohol, ends up inhibiting serotonin and melatonin production. Since over time marijuana use will reduce both serotonin and melatonin, they will eventually quit working or the person will become totally dependent on the drug.2

There are hundreds of brain imaging studies that have been done and have demonstrated that marijuana diminishes brain function as it damages neurons. Additionally, studies have shown that it also saps motivation, energy, and can lead to problems with skin, teeth and, hair.1 Marijuana also has negative effects on the heart and reproductive organs and their function.2Another scary finding is that chronic marijuana use can lead to severe anxiety.

Marijuana and Memory

In a study that appeared in the journal Cell, researchers found that the active ingredient in marijuana, tetrahydrocannabinol (THC), weakens the synapses (the connections between brain cells) in the hippocampus which is a structure in the brain crucial for memory formation. This study was done using microelectrodes implanted into the brains of anaesthetized rates.


I would use caution when considering marijuana use as it can impair and decrease brain function including brain processing speed, serotonin and melatonin levels, and sleep. It can also lead to problems with decision making, attention, focus, executive functioning, memory, language and lead to severe anxiety. Lastly, dependency can develop and it can take several months for the body to fully detoxify itself from TCH as it is stored in our fat cells. People may not return to their “true self” for several months after stopping use, and if withdrawal is severe may need clinical help. Lastly, the marijuana plant is not what it used to be. It has been modified and hybridized so much that it is 10 to 25% more potent than it was during the Woodstock era. The form of marijuana we have in our day in age is not “natural”.

1. Change Your Brain, Change Your Body: Use Your Brain to Get and Keep the Body You Have Always Wanted
2. The Mood Cure: The 4-Step Program to Take Charge of Your Emotions–Today

Thanks BARC for composting food waste on our site, providing us with copious free organic matter and feed for pigs and chickens! Let's keep closing the loops!