American scientists have discovered that following a healthy lifestyle will not protect you from the majority of cancer cases. They have found that malignant tumors are the result of genetic mutations, rather than obesity, poor diet or lack of exercise.
The researchers from the School of Medicine at Johns Hopkins University in the US found that two-thirds of cancer victims are faced with the cumulative effect of random errors in the genes, which preconditioned the development of malignancies. In this case, cancer is not determined by one’s lifestyle. Until recently, scientists believed that 30 to 40% of all cancer cases could be avoided if people had a healthy lifestyle.
However, American researchers have come to a different result. The study authors observed the ratio of random mutations in the stem cells of various body tissues, which can cause cancer. These mutations are errors that occur in our DNA during the process of cell division and reproduction. The more such mutations occur, the greater the probability of cancer is.
The scientists observed 31 types of cancer, analyzing the number of stem cells divisions in each type to determine the risk of cell mutations. They found that 65% of all cancer cases could be attributed to cell division, and only 35% had hereditary reasons or were triggered by external influences, i.e. wrong lifestyle.
According to the authors, genetic mutations most often cause cancer in the brain, head and neck, thyroid, esophagus, lungs, bones, liver, pancreas, skin, testes and ovaries. An unhealthy lifestyle is responsible for such cases of tumors, as skin cancer (basal cell carcinoma), throat, thyroid, lung cancer (in case of smokers), liver cancer (alcoholism) and intestinal cancer.
