Prevalence of factors related to the bone mass formation of children from a cohort in Southern Brazil.

Introduction: The amount of bone mass acquired in the early stages of life is an important determinant of its peak and future risk of osteoporosis and fractures. Objective: To describe the prevalence of factors that contributes to the formation of bone mass in children of a Southern Brazil cohort. Methods: A retrospective cohort study with hospital screening of all births (2741) occurred from September/2002 to May/2003 and monitoring of a random sample of 30.0% of these (one, three and six months and eight years old). During the eight years old visit, a questionnaire containing questions related to food and physical activity was applied. Results e Discussion: Of the 616 children studied, 51.3% were male, 70.3% Caucasian, about half belonged to economic class C, 20.5% were overweight, 16.9% were obese and 71.2% were sedentary. As for food intake low consumption of fruits, vegetables, dairy products, meat, cereals and tubers was noticed. Vitamin D administration in the first six months of life was followed by 14.1% of premature, 16.1% of infants with low birth weight, 24.2% of weaned in the first month and only 16.4% at three months. Conclusion: The evaluated children have low nutrients consumption, including calcium, inappropriate vitamin D administration in the first semester of life, little regular physical activity and high prevalence of overweight and obesity are factors that can impair the formation of bone mass.