Marijuana use has been associated with a mental health problem for a long time. A recent study showed long-term marijuana use has a disastrous impact on mental health due to the evidence that the drug can alter human brain's reward system that increases negative emotions.

The research explained that there is a sufficient evidence that pot use reduces dopamine level. Dopamine is a neurotransmitter released by our brain and it has functions in movement, pleasure, learning, and so on.

Low dopamine levels have been linked with depression, lack of energy and motivation, fatigue and mood changes. Dopamine deficiency is seen in some medical conditions such as Parkinson's disease and attention deficit hyperactivity disorder (ADHD).

The study was conducted by the Medical Research Council (MRC) Clinical Sciences Center at Imperial College London in the United Kingdom with Prof Oliver Howes as a study leader. The result of the study was recently published in the academic journal Nature.

There are 22.2 millions of marijuana users in the United States, based on data from the 2014 National Survey on Drug Use and Health (NSDUH). There is a recent growing concern after Donald Trump was elected as the President of the United States that his nomination for Alabama Sen. Jeff Sessions as the upcoming attorney general will undermine marijuana legalization, as reported by the The Guardian.

The study revealed how a compound called tetrahydrocannabinol (THC) in marijuana produces varied effects on dopamine level, including increased nerve firing and dopamine discharge responding to acute THC. Based on this finding, the team believed why people who have been engaged in marijuana use for the long term can develop a higher risk of suffering from mental illness.

While in animals, current studies show marijuana use can increase dopamine level, offering an explanation on why people are addicted to drugs. However, Prof. Howes noted that animal studies are too short.

However, researchers also spotted some gaps as studies examining what happens to dopamine level when marijuana use is decreased. According to Prof. Howes, it is important to understand that animal studies show the effects of long-term cannabis use on the developing brain in a controlled way that is impossible in human studies."

Related