Children and food have an interesting relationship. For example, they may love something this week that they won't touch next week or they may decide that green foods will never again cross their lips. Keeping up with their fickle food preferences is challenging enough for a parent, and sometimes the food your child eats may be linked to whether or not he has a dry night.

Kathleen, a mother of four from Culver City, Calif., believes that some foods seem to affect her 8-year-old son's ability to stay dry at night. "I've noticed some connection, depending on the kind of foods he's been eating, but it hasn't been perfectly clear," says Kathleen. "I find that my son does better when his diet contains fewer processed foods and more iron." Foods such as meats and green leafy vegetables like broccoli, spinach and other greens are high in iron.

Anne Boisclair-Fahey, a pediatric nurse practitioner at the University of Minnesota, also believes that such a connection may exist -- for some children. "Some children that wet the bed will benefit from restricting certain foods from the diet," says Boisclair-Fahey. "Other children may not. Bedwetting can be caused from a number of factors -- diet is only one of them."

According to Sue Dengate, author of (make sure all links open up in another window) Fed Up: Understanding How Food Affects Your Child and What You Can Do About It (Random House Australia, 2003), intolerances to food can increase your child's chances of wetting the bed. "I always like to distinguish between true food allergies – a quick reaction to food proteins involving itching or swelling – and food intolerances, which are a delayed reaction to chemicals in a wide range of foods," she says. "It is the food intolerance which impacts bedwetting. Food intolerance is much more common than food allergy, but much harder to detect."

Food intolerance tends to run in families. However, Dengate says, "We find that all children are different – some [children who wet the bed] are affected by artificial colors or preservatives."

So how can you tell which foods affect your child's bedwetting? According to Boisclair-Fahey, parents should take a hard look at five C's which include: caffeine, carbonation, citrus, chocolate and extra doses of vitamin C. These foods tend to increase the amount of urine the body produces, which makes it difficult for your child to have a dry night. Of course, the causes of bedwetting vary by child, so even though food may not be a main cause, it might play a partial role.

In addition to caffeine, chocolate and carbonation, Dengate feels that parents should test bread, as well. Dengate conducted a study, which was published in the (open in a new window) Journal of Paediatrics and Child Health on the effects of calcium propionate, a preservative widely used in bread, on children's behavior. She found that the children in her study who wet the bed improved when they eliminated the additive from their diet and, for some of them, the bedwetting returned when they ate bread containing the preservative.

"For parents who want to try the dietary approach, some will see a difference just by changing bread and drinks," says Dengate. "This means switching to bread without calcium propionate preservatives, which might mean buying specialty loaves such as French or Italian and encouraging children to drink bottled water instead of juice, milk or sodas."

According to Dengate, dairy foods, such as milk, also tend to irritate the lining of the bladder, causing bedwetting. Because so many children have an undiagnosed intolerance of dairy it should be one of the first foods you test, she says, along with food colors and preservatives.

The best way to pinpoint exactly which foods are causing the problem is to do a three-week elimination diet, removing all foods from your child's diet that could be affecting his bedwetting. Then you can carefully reintroduce the foods, one at a time, back into your child's diet to find the true culprits. Consult your child's doctor before implementing any changes in your child's diet.

One of the most important things to remember is that most childhood nocturnal bedwetting is simply a matter of physical development and maturity. Though foods may have an impact on how often your child wets at night, chances are that a change in diet won't completely eliminate the problem. Understanding, love and time are the most effective weapons against nocturnal enuresis.