The dilemmatic role of medicine in adolescent obesity from the perspective of reduced natural selection

Abstract

Abstract Objective Relaxed natural selection has been indexed with the Biological State Index (Ibs), which indicates the opportunity for an average member of a population to pass genes to the next generation. This study explores the correlation of Ibs to adolescent obesity prevalence.Methods Population level variables (adolescent obesity prevalence, self-calculated Ibs, GDP, urbanization and calories) are extracted from or calculated with the United Nations data agencies for the correlation analyses. To examine the Ibs-adolescent obesity relationship, the five non-normally distributed variables are analysed in curvilinear regression models with raw data and linear regressions with log-transformed data. Countries are grouped for exploring the regional Ibs-adolescent obesity correlations.Results Linear correlation and the first order curvilinear regression identified that Ibs-adolescent obesity correlation is significant, and this relationship remains in the third order curvilinear regression and partial correlation when the confounding effects of GDP, urbanization and calories are removed. Ibs-adolescent obesity correlation also presents in different country groupings. It is highlighted that Ibs-adolescent obesity is significantly stronger in developing countries than developed countries. Stepwise multiple linear regression identified Ibs as the second most influential risk factor for adolescent obesity. Caloric intake does not show significant effects on predicting adolescent obesity in both enter and stepwise regression models.Conclusions Reduced natural selection may drive obesity associated genetic background to accumulate in population through allowing people to participate in reproduction. The magnitude of reduced natural selection correlates with adolescent obesity prevalence. This suggests that reduced natural selection is another major risk factor for adolescent obesity.