Women’s stomachs are full for longer than men’s after drinking beer or soft drinks. This may explain why women often drink more slowly, and feel bloated more quickly.
The study, published in the Journal of Nutrition, involved 17 women and 17 men, who were asked to fast for three hours before participating. Then they were given half a litre of beer on one day and on another, half a litre of a soft drink, which they had to drink up in 20 minutes. Then they had an MRI scan.
Researcher Guido Camps and his colleagues at Human Nutrition discovered that the liquid stayed in women’s stomachs longer. The amount of gas produced was the same in men and women, which suggests that the volume of liquid is the main explanation for the bloated sensation. The scientists cannot say much about the role of carbonic acid as the was no control group in this study that got a drink without carbonic acid. Camps says the women in the study reported more nausea than the men did. ‘That is probably a direct result of the slower emptying of the stomach.’
Camps does not yet have a precise explanation of the difference found between men and women. ‘Our guess is that the slower emptying is caused by certain female hormones that slow down the stomach. But we haven’t measured the hormones, so we cannot say anything more about that now.’
According to Camps, the results are relevant to medical and nutritional research. These currently use standard times for the length of time it takes the stomach to empty. ‘Our study, along with a number of previous studies that point in the same direction, suggests there is a need for separate references for men and for women.’