Smoking marijuana during adolescence can have serious consequences for health, since according to a recent study the consumption of this substance in this stage of life can affect the development of the brain and cause a deterioration that alters intellectual abilities such as memory, understanding verbal, or the speed at which the information is processed.

Although marijuana is used for medical purposes in the treatment of certain diseases such as cancer or multiple sclerosis, that does not mean that smoking cannabis is beneficial to health.

To verify the impact of marijuana use in an especially vulnerable stage of life such as adolescence, researchers from King's College London, Duke University in the United States, and the University of Otago in New Zealand have carried out a study - which has been published in 'PNAS' - in which 1,037 volunteers have participated, who were followed up from birth (in 1972 and 1973) up to 38 years of age.

Those who had started smoking younger marijuana were also those who had a greater deficit in their intellectual performance

The volunteers performed neuropsychological tests when they were 13 years old and had not yet begun to use cannabis, and again when they reached 38 years old, an age at which some were already habitual users of marijuana. The scientists found that people who had greater dependence on cannabis were those who had a greater cognitive impairment but, most remarkable of the study is that they could see that those who had started smoking younger marijuana were also those who had a greater deficit in his intellectual performance.

Another important piece of information revealed by the study is that intellectual deterioration affected both those who had used cannabis regularly during their adolescence, and those who only consumed it on an occasional basis. Even in the case of discontinuing consumption later, the neuropsychological function was not fully restored.

Researchers acknowledge that more studies are needed to determine the quantity, frequency and age of onset that generate neuropsychological deterioration, but warn that puberty is a critical stage in the development of the brain, characterized by the maturation of neurons and the synaptic reorganization, and that a chronic consumption at these ages has negative consequences on the intellectual capacity.

Marijuana and the Young Brain (November 2019).