Background: The aim of the present study was to determine the prevalence of overweight and obesity in volunteers supported by a primary healthcare center in Goiania city. Methods: The prevalence of overweight and obesity was calculated using data from a public primary healthcare center in the city of Goiania, Brazil, which serves approximately 10,000 patients. Data were collected between September and October 2011 from individuals aged 20 years or older via medical records. Seven hundred and eighty-nine patients participated in the present study, 546 women (43.9 ± 16.4 years, 66.2 ± 13.3 kg, 1.6 ± 0.1 m) and 243 men (46.0 ± 17.2 years, 73.7 ± 14.7 kg, 1.7 ± 0.1 m). RESULTS: The analysis of variance indicated no significant difference in BMI distribution between genders (p = 0.0763), however, there was a significant difference between age groups (p = 0.0000) and a significant association between gender and age (p = 0.0196). The percentage of overweight and obesity was above 40% and the percentage of obese was 15% in the population studied. The results show a high prevalence of overweight and obesity among adults, especially the elderly. Conclusions: There is a high prevalence of overweight and obesity among adults and the elderly, with a significant difference between age groups and an increase in BMI with age.