FRUIT JUICE MALABSORPTION - NOT ONLY FRUCTOSE

Malabsorption of free fructose, when ingested in excess over glucose, is considered a significant factor in apple juice induced diarrhoea. A bsorption of the carbohydrates in fruit juices was investigated by mea ns of the hydrogen breath test in 15 healthy children aged 2.2-6.4 yea rs, consuming 15 ml kg(-1) of each juice with a maximum of 375 mi. Inc omplete absorption was found following the ingestion of apple juice (5 /5), grape juice (10/10) and bilberry juice (8/10), although the last two contain equivalent concentrations of fructose and glucose. When th e same tests were repeated after yeast treatment of the juices, which leads to major reductions in fructose and glucose contents, malabsorpt ion was found to persist. No symptoms were observed following any of t he tests. Our results suggest a significant role for other carbohydrat es than fructose, possibly those originating from the fruit skin, with respect to fruit juice-induced breath hydrogen excretion.