The suggested link between a high intake of dietary fat and obesity has led to a proliferation on the market of reduced fat foods. The preceding year has seen the publication of more long‐term studies investigating the effects of reduced fat and fat substituted foods on energy intake, fat intake and body weight. Effects on the proportion of the diet consumed as fat are encouraging (with most studies showing a decrease towards dietary recommendations), whilst effects on energy intake and body weight remain equivocal. Curr Opin Lipidol 9:41–45. © 1998 Rapid Science Ltd