With obesity on the average more than the volume of the kidneys, liver and pancreas, and this change correlates with the risk of cancer of the relevant authorities. The authors of the article, a Preprint of which is published on the bioRxiv portal, suggest that the relationship of obesity and cancer risk is due to the large number of cells in organs and increase the likelihood of mutations.
Obesity is one of the main factors of risk of development of cancer of various types. In recent decades, the number of people with obesity is increasing worldwide, but the mechanisms of influence of overweight on the risk of cancer is not yet clear. For example, it is shown that in malignant tumors of people with obesity mutational load, mutation rate — not different from people of normal weight.
Scientists from the U.S. and France headed by Christian Tomasetti (Cristian Tomasetti) from Johns Hopkins University suggested that the risk of developing cancer increases with obesity is not due to changes in individual cells, and for statistical reasons. According to the researchers, people with overweight of the size and number of cells in them more, which means higher chance of having mutations.
In a previous study, Tomasetti group showedthat the number of cells (or rather the frequency of their division) are associated with risk of development of malignant tumors. Now researchers have tested the influence of excess weight on organ weights and the number of cells in them. For this, computed tomography calculated the size of the kidneys, pancreas and liver 750. The volume of the organs compared with the body mass index of study participants.
People with high body mass index the size of the internal organs were large: while body mass index greater than 50, the volume of organs could be twice that of people of normal weight. To explain the increased size of the bodies of a large number of subcutaneous or visceral fat (they are not included in the composition of the bodies by computer tomography) or an increased number of fat cells (it is knownthat in the kidney, pancreas and liver in obesity it changes slightly) not — so grows mainly Nazirova tissue — the parenchyma.