[Body mass index increase after the age of 20 and associations with risk or protection factors for chronic non-communicable diseases].

OBJECTIVE To examine sociodemographic risk or protection factors for chronic non-communicable diseases (CNCDs) that may be associated with increase in body mass index (BMI) after the age of 20. METHODS Cross-sectional analysis based on data from 769 women and 572 men who participated in the 2005 Surveillance System for Risk factors for CNCDs, Florianópolis, Brazil. BMI increase was defined in percentage as the difference between BMI in 2005 and at age 20. RESULTS Since the age of 20, most of the respondents had increased their BMI by more than 10%. In multiples analysis, independent correlates of BMI increase were: advancing age, low education (women), being married (men), not working, low self-rated health, high blood pressure, high cholesterol/triglyceride levels (men), going on a diet, sedentarism and having been a smoker (women). CONCLUSIONS Health promotion strategies to prevent weight gain need to be targeted to groups and should mainly consider sociodemographic factors.