Question: My son has been complaining recently about tummy aches after eating certain fruits like grapes and watermelon. Lately, he can’t seem to tolerate apple juice even though it’s his favorite drink. Could the fruit be causing his pain? I thought that feeding him fruits was a healthy choice?
Answer: Generally, fruits and vegetables are a healthy choice for children. In fact, according to the U.S. Department of Agriculture, it is recommended that children ages 2-3 eat 1 cup of fruit per day, those ages 4-8 consume 1-1.5 cups, those ages 9-13 consume 1.5 cups, and those 14-18 consume 1.5-2 cups of fruit per day.
Fruits, fruit juices and some vegetables, however, contain a naturally occurring sugar known as fructose. Fructose is also found in honey, table sugar and high-fructose corn syrup used to sweeten many processed foods and beverages. Some people may suffer from fructose intolerance, a condition in which the body’s digestive system doesn’t absorb fructose properly. This can result in abdominal pain, bloating, constipation, diarrhea and gas for some.
According to a 2010 study by the American College of Gastroenterology (ACG), fructose intolerance is common in children with recurrent or functional abdominal pain, but the condition can be effectively managed with a low-fructose diet. It seems the condition is more prevalent in teenage girls who suffer from chronic abdominal pain, the study’s authors said.
According to the study, “Fructose Intolerance/Malabsorption and Recurrent Abdominal Pain in Children,” fructose intolerance in children is typically diagnosed by exclusion, meaning other gastrointestinal conditions like Crohn’s disease and ulcerative colitis are ruled out as the cause of the abdominal pain.
Once these have been ruled out, your doctor can test your son for fructose intolerance by administering a fructose breath test, which measures the rise in hydrogen in a person’s breath after an oral dose of fructose, according to the Cleveland Clinic Children’s Health Team.
If your child is diagnosed with fructose intolerance, you should see a registered dietitian to determine foods that are OK to eat and those that should be avoided. Generally, people with fructose intolerance should limit their intake of high-fructose foods such as juices, apples, grapes, watermelon, asparagus, peas and zucchini, according to the Mayo Clinic.
While it may be difficult to both find foods with low fructose and get your son to not eat foods with high fructose, there is good news for those with fructose intolerance: The ACG study found that more than half of patients who are fructose intolerant are able to maintain a low-fructose diet and are able to notice an immediate improvement in their symptoms.