Smoking cannabis poses a health risk. Specifically, smoking five or more joints a week is harmful. However, in certain population groups, smoking any amount of cannabis poses a risk to their health. In this position are, for example, those under 21 years of age, pregnant women, lactating women and patients with heart, respiratory or mental problems such as psychosis, depression, bipolar disorder, anxiety disorders and addiction, among others. This is one of the conclusions shared by a group coordinated by Clínic-IDIBAPS professionals, including Mercè Balcells, head of the Addictive Behaviors Unit at Clínic Barcelona, ​​Hugo López, head of the IDIBAPS Addictions group and vice president of Socidrogalcohol , Laura Nuño, clinical psychologist and Clara Oliveras, psychiatrist and researchers from the same group.

Cannabis is one of the most consumed drugs in the world, along with tobacco, alcohol and cocaine. Specifically, it is estimated that 2% of the world population consumes it daily. It has some therapeutic properties, as it reduces chronic pain and has anti-inflammatory effects. Sometimes it is administered to some patients receiving chemotherapy, but always under strict medical supervision. Frequent cannabis use carries significant health risks. The 2021 report from the Spanish Observatory on Drugs and Addictions indicates that one in 10 individuals between the ages of 15 and 64 used marijuana or cannabis and was exposed to the effects of THC in the last year. THC is a chemical substance in cannabis that has psychotropic effects on those who consume it, distorts the perception of reality and produces addiction.

In Spain, the habit of smoking cannabis is normal for 2.8% of the population who admit to consuming a cannabis cigarette daily, according to the EDADES 2022 report, carried out by the Government Delegation for the National Plan on Drugs. This survey is carried out at home throughout the national territory, in the general population residing in homes and aged between 15 and 64 years. In 2022, the sample was 26,344 people, and it was observed that cannabis is the illegal substance with the highest prevalence of consumption. 40.9% had used cannabis at some time in their lives, 10.6% in the last 12 months, 8.6% in the last month. In recent years, occasional consumption seems stable, but daily consumption has increased to the aforementioned 2.8% in 2022 from the 1.7% existing in 2007. These data place Spain, in percentage terms, among the European countries that consume the most cannabis, along with Luxembourg and Portugal.

By age, the prevalence of consumption is higher in the group between 15 and 24 years of age. 22.6% of young people of this age used cannabis in the last 12 months (27.2% of boys and 17.8% of girls) and 17.1% in the last 30 days (21.5 % of boys and 12.5% ​​of girls). The comparison with other drugs consumed in the last year shows that those with the highest consumption are alcohol (76.4%), tobacco (39.0%) and hypnosedatives with or without a prescription (13.1%), followed by cannabis (10.6%) and cocaine (2.4%). Regarding the combined consumption of drugs, cannabis appears in 61.4% of the cases in which three psychoactive substances are consumed. In this case, practically every time cannabis is accompanied by tobacco and alcohol.

The illegal substance that is perceived as the most accessible is cannabis, since 56.9% believe that they could get it easily or very easily in 24 hours. In second place is cocaine (40.3%). Those surveyed consider that the most important measures to solve the drug problem are training (88.3%), offering voluntary treatment to consumers (81.6%) and advertising campaigns (79.6%). 33.8% advocate the legalization of cannabis, which means a slight drop in support for this option, which in 2020 was supported by 36.5%.

It is worrying that 15% of the adult population (between 15 and 65 years) considers that cannabis use does not harm health. This percentage is 11% among adolescents (14 to 18 years). This low perception of risk, added to unreliable sources of information or directly with commercial interests, makes it difficult for the population to have access to credible health messages based on scientific evidence.

Faced with this situation, it is necessary to transmit to the citizens several clear ideas about cannabis. The first is that its consumption is not safe. Its therapeutic use is found, mainly, in some of the components of cannabis, from which the treatments are derived, but not in the cannabis itself. In addition, the evidence of its usefulness is scarce and any consumption for therapeutic purposes must be supervised by a health professional. On the other hand, it has been shown that patients with mental health problems worsen their condition when they consume cannabis or alcohol. Another of the dangers of smoking cannabis is the risk of heart or lung problems. In short, smoking any amount of this substance carries a health risk and it is important that there is a general awareness about it.