Every day in Spain more than 150 people die as a result of tobacco smoke, i.e. 55,000 Spaniards die each year as a result of tobacco smoke. In the world, it is estimated that more than 5 million people die from tobacco smoke every year. This makes smoking one of the most harmful habits in our society. Today we could say that smoking is a self-inflicted pandemic that we suffer in a surprisingly silent manner.

Tobacco addiction is due to nicotine, a drug contained in cigarette smoke. In addition, it contains hundreds of other toxic substances such as nitrosamines, hydrogen cyanide, formaldehyde, lead, arsenic, ammonia, benzene, carbon monoxide and polycyclic aromatic hydrocarbons. Some of these substances are naturally occurring in the tobacco plant, others are produced as a result of its combustion.

Their consumption is the cause of the onset or aggravation of a multitude of diseases. Without going any further, the respiratory problems of smokers make them one of the main risk groups for COVID-19. In turn, recent programs of study suggests that tobacco smoke increases the production of the protein that the SARS-CoV-2 virus uses to penetrate lung cells. In addition, many other diseases are associated with smoking: heart attack, respiratory failure, stroke, diabetes, tuberculosis, asthma, erectile dysfunction, rheumatoid arthritis, cataracts, pregnancy problems and, of course, cancer.

Tobacco contains about 70 carcinogenic molecules, substances that have the capacity to cause cancer in our body. These molecules are transported in tobacco smoke to the lungs, where they are absorbed. They are then distributed throughout the body and can penetrate any of our cells, with the risk of damaging their genetic material. This damage could cause changes in the cell's behavior, turning it into a malignant cell with the capacity to divide uncontrollably and spread throughout the body. This is the origin of cancers caused by tobacco smoke. With more than 20,000 deaths per year in Spain, lung cancer is the subject cancer most strongly associated with tobacco consumption. Smoking causes almost nine out of ten cases of lung cancer. In addition, smoking is also related to the increased risk of developing many other types of tumors, such as leukemias or carcinomas of the bladder, mouth, head and neck, esophagus, colon and rectum, stomach, pancreas, liver or kidney. At final, smoking can cause cancer in almost any part of a smoker's body.

At this point, it is important to note that the people around the smoker also inhale the smoke from his or her tobacco. This is what is known as passive smoking or second-hand smoking. It could be thought that the damage produced in a passive smoker is minimal or anecdotal, but this is not the case. Smoke can cause the same diseases in them as in the active smoker, including, of course, cancer. It is estimated that one in ten people who die from tobacco smoke are killed by tobacco consumed by others. Fortunately, the level of exhibition to tobacco smoke has been considerably reduced in recent years thanks to the regulation of smoking in public places. Thousands of lives have been saved and we must show our gratitude to the people who have worked so hard to make this possible, often in the face of powerful political and economic interests. If the COVID-19 pandemic has taught us anything, it is the importance of each one of us making ourselves manager of our actions, respecting and preserving the health of others. Therefore, it is also very grateful for the attitude of those smokers who respect the most basic rules of hygiene and coexistence, beyond legal impositions.

Finally, it is important to remember the advances that have been made in the early diagnosis and treatment of cancer through research. Today, more than half of the patients treated are cured. In the case of lung cancer, scientific progress has made it possible to discover indicators to predict the prognosis of patients and to define more effective anti-tumor strategies. Specifically, recently at Cima University of Navarra we identified a group of proteins whose high presence in patients determines a worse evolution of their disease and we have also proposed new therapeutic strategies based on the reactivation of the patient's immune system. These advances are allowing the development of novel personalized therapeutic strategies such as targeted therapy or immunotherapy, treatments that are already being applied or are being evaluated in clinical trials, with very encouraging results. Regarding diagnosis, several programs of study have demonstrated the usefulness of screening programs in high-risk individuals, as they allow the disease to be diagnosed at very early stages, which significantly improves survival rates fees . In this regard, several years ago, Clínica Universidad de Navarra pioneered the introduction in Spain of an international early detection program for lung cancer. In addition, treatment for this cancer - although still at development- is also starting to be provided in its new Proton Therapy Unit. Having said this, let us not forget that the most effective measure to preserve or improve our health is to reduce tobacco consumption and protect third parties, mainly children, the sick and the elderly, from exhibition .