We examined the effects of 5 g red pepper powder in soup preload given at breakfast on food intake, blood pressure, body core temperature, hunger, fullness and thirst scores in 29 female collage students. All subjects received two kind of soup preloads in random order. After ingesting a soup, subjects ate other food items as a breakfast ad libitum. Two soups were of the same composition and volume but differed only in 5 g red pepper. So one soup designated as "beef-vegetable" and the other soup designated as "red pepper". Red pepper soup consumption significantly enhanced energy and macronutrient intake by 17%. The hunger scores after test meals were inversely correlated with energy and nutrient intake in beef-vegetable meal. However, the postprandial hunger scores were not correlated with energy and nutrient intakes in red pepper meal. The fullness scores at 90 min after the red pepper meal were inversely correlated with energy and nutrient intake whereas the fullness scores after beef-vegetable meal were not correlated with energy and nutrient intake. These results suggest that hot red pepper ingestion may desensitize some gastrointestinal vagal afferents and disturb feeling of hunger and fullness. The postprandial changes of body temperatures in red pepper meal were higher for a longer time in comparison with those in beef-vegetable meal. For the red pepper meal there frequently were higher correlations between blood pressures and anthropometric measurements, compared to those in beef-vegetable meal. These results might be explained partly by the enhancing effects of capsaicin on thermogenesis and sympathetic nervous system activity. It is concluded that the ingestion of spicy soup with red pepper can increase appetite, energy and nutrient intakes in Korean females, and this effect might be related to disturbed feeling of hunger and fullness.hunger and fullness.