[Historical biometrics of young Castilian males: the impact of income and nutrition on their height, 1858-1959].

Introduction: Background: anthropometric studies have made it possible to measure the evolution of well-being in Spain and under a historical perspective, but the precise effect of income on height has not yet been calculated. Objective: the purpose of this paper is to identify the periods in the life trajectory of young people in which food availability was the most important determinant of their physical growth. Results: the model estimated using ordinary least squares shows that the wage income received by the parents of the young male in the first three years of life and the three years immediately prior to the onset of adolescence explain up to 60 % of his height at the age of 18. All the coefficients of the regressors of the models presented are significant at 0.99 %. According to these calculations, the type of nutrition received by the young person in the period between 11 to 14 years of age was a determining factor in his or her evolutionary process. In addition, the calculations show that food deficiencies were to blame for recurrent periods of loss of well-being, especially in the second half of the 19th century. Conclusion: nutritional deficiencies caused by low wages and poor nutrition have for centuries hampered the physical growth of Castilian youth.