The rising rate of obesity has been blamed on increased consumption of sugar-sweetened soft drinks, such as carbonated sodas, which fail to satisfy hunger. The objective of the present study was to compare the effect on appetite and energy intake of a sugar-sweetened beverage (cola) and a chocolate milk drink, matched for energy content and volume. It was hypothesised that chocolate milk may be more satiating because of its protein content. Twenty-two healthy young men (age 23 (SD 1 x 8) years) of normal weight (BMI 22 x 2 (SD 1 x 5) kg/m2) were recruited to the randomised cross-over study. Visual analogue scales were used to record subjective appetite ratings every 30 min on each of two test days. A drink of 500 ml cola or chocolate milk (900 kJ) was ingested 30 min before an ad libitum lunch. Satiety and fullness were significantly greater (P=0 x 0007, P=0 x 0004, respectively) 30 min after chocolate milk than after cola. Ratings of prospective consumption and hunger were significantly greater after cola than after chocolate milk, both immediately after preload intake (P=0 x 008, P=0 x 01, respectively) and 30 min afterwards (P=0 x 004, P=0 x 01, respectively). There was no significant difference (P=0 x 42) in ad libitum lunch intake after ingestion of chocolate milk (3145 (SD 1268) kJ) compared with cola (3286 (SD 1346) kJ). The results support the hypothesis that sweetened soft drinks are different from milk products in their impact on short-term hunger and satiety, although differences in subjective appetite scores were not translated into differences in energy intake.