Smoking status relationships with the food and fluid intakes of free-living humans.

OBJECTIVE: The relation of cigarette smoking to food and fluid intakes was studied.
METHODS: Ninety-nine smoking and 551 non-smoking free-living adult humans provided a detailed record of their eating and drinking in 7-d diaries.
RESULTS: Cigarette smoking was associated with significant changes in overall intakes and meal pattern. Smokers had higher intakes of fluids in the form of drinks due to higher levels of alcohol and coffee/tea consumption. Smokers were less hungry but more responsive to social facilitation and time of day. There were also substantial gender differences in smoking relations to intake, with male smokers tending to have higher overall and meal intakes particularly of fats than non-smokers, whereas female smokers tended to have lower overall intakes, fewer meals, and lower amounts of carbohydrates than non-smokers. Male smokers tended to be less responsive to their before-meal stomach content, their level of hunger, and the palatability of the meal than non-smokers, whereas females tend to be more responsive to all of these influences on meal size.
CONCLUSION: These results suggest that smoking has very few direct simple effects on intake but rather influences intake indirectly through its covariation with alcohol and caffeine intakes and with dietary restraint and that smoking has different, sometimes opposite, influences in males and females.