The results of an interesting study looking at the relationship of caffeine intake and bedwetting were published Dec.17, 2010, in www.jpeds.com. Enuresis (bedwetting) and caffeine consumption were not significantly correlated in this group of 201 five to twelve year old children. Because of the known diuretic effects of caffeine, it has been recommended over the years that children with bedwetting have their caffeine restricted. In this study, children who consumed caffeine were less likely to wet the bed than children who did not drink caffeinated beverages. Therefore, removing caffeine from children’s diets, although a logical treatment recommendation for bed wetting, was not supported by the data. It seems that there are multiple mechanisms that contribute to bed wetting and the increased diuretic effect of the caffeine is not directly related.
The children who consumed the largest amount of caffeine did not have the highest incidence of bedwetting but they did sleep fewer hours at night. In the older children, aged 8 to 12, the average amount of caffeine consumed was equivalent to three 12-ounce cans of soda per day. These children slept an average of 8.47 hours per night, which is less than the recommended 9 hours per night for this age group.
So it seems that telling your children that drinking caffeine/sodas will cause them to wet the bed may not be the truth. We do know that caffeinated drinks contribute to less hours of sleep per night, and sodas contribute to obesity and dental caries so it does seem prudent to continue to limit your children’s intake of caffeine for other reasons.
Link to see entire article, http://download.journals.elsevierhealth.com/pdfs/journals/0022-3476/PIIS0022347610009935.pdf