The waist-to-hip circumference ratio (WHR), as an indicator of body fat distribution is related to several clinical diseases. Whether one can reduce this ratio with weight loss is still unconfirmed and may differ between sexes. The degree to which WHR changes with weight gain is also unclear. Changes in waist and hip circumferences and WHR accompanying changes in weight over 5 years were examined in 3,753 black and white men and women initially ages 18-30. Those who gained weight increased their WHR and in most cases those whose weight remained stable increased their WHR. Those who gained the most weight had the greatest increases in WHR. Men had greater increases in WHR per kg weight gain than women. In general, weight loss was accompanied by a decrease in the WHR. However, in those whose initial WHR was below the median, weight loss was associated with an increase in WHR. Smokers and black males also had increases in WHR with weight losses up to 4.9 kg.