Cannabis refers to a group of three plants, namely Cannabis sativa, Cannabis indica, and Cannabis ruderalis, whose flowers are harvested and dried and then used to form one of the most common drugs in the world. These drugs act upon the central nervous system altering brain function. They result in a temporary change in perception, mood, consciousness, and behavior.

According to the research on cannabis use in Peru done in 2003, adults as young as twelve years were using cannabis. Similarly, in 2014, a study was conducted in Chile, which showed that 31.5% of Chileans aged 12 – 64 had used cannabis. However, only 10.3% of the population in Peru has consumed cannabis. Chile has the highest per-capita use of marijuana in Latin America, even though all production and public consumption of cannabis is illegal. Chile imports a large amount of cannabis from its neighbors, particularly Paraguay and Peru.

For most countries, the consumption of cannabis begins at fifteen years, which is indicated by the research carried out in Belgium in 2004, with 10.4% of the population aged 15 – 64 years using cannabis. In Romania, the research carried out in 2008 showed that 7.4% of the population aged 15-64 years consumed marijuana. The research carried out in 2007 in Ghana showed that 21.5% of the population between 15 and 64 years consumed cannabis. Similarly, in Italy and Greece, the study was carried out in 2005 for Italy and 2004 for Greece. The research highlighted that 29.3% of the population in Italy and 8.9% of the people in Greece used cannabis.

For countries like China, Nigeria, Germany, Lebanon, and South Africa, research shows that consumption of cannabis begins at eighteen years. The research carried out in China in 2002-2003 shows that only 0.3% of the population uses cannabis, which is the lowest use of marijuana in the world. In Germany, the research carried out in 2003 shows that 24.5% of the population aged 18 – 59 years uses cannabis. The research carried out in South Africa from 2003 – 2004 shows that 8.4% of the population over eighteen years uses cannabis. In Nigeria, about 2.7% of the population over eighteen years in 21 out of its 36 states uses marijuana.

Japan and Israel have the highest ages of introduction to the use of cannabis. In Japan, the research carried out in four of its metropolitan areas in 2002 -2003 indicates that only 1.5% of the population over 20 years uses cannabis. For Israel, research carried out in 2002 – 2004 shows 11.5% of the population over 21 years uses marijuana.

We can explain the differences in adult use of cannabis in different countries by the gap in the collective knowledge about cannabis and the regulations around the use of cannabis in different countries. Where people believe that there are serious risks associated with the use of marijuana, the numbers are low.