This is the first double blind prospective study designed to evaluate the effects of fruit juice feedings during diarrheal disease in young children. Two commonly available juices were selected and compared with water intake, as part of an age appropriate dietary intake. One juice contained equimolar quantities of glucose and fructose (WGJ) and the other one provided a higher fructose to glucose ratio and contained sorbitol (AJ). All patients improved while being fed water or any of these 2 juices. However those receiving juice had more stool losses than those fed water, highest being among the patients fed AJ. This was a significant finding during the first day of treatment, not thereafter. On the other hand the children fed juice ingested more calories and gained more weight than those fed water, those fed WGJ having the best response.
Acute gastroenteritis continues to be a common illness among infants and children worldwide. The disease causes an estimated 2 million deaths annually among children in the developing world. In the United States diarrhea accounts for more than 1.5 million outpatient visits, 200,000 hospitalizations and 300 deaths per year . Children younger than 5 years of age are at much higher risk of death from diarrhea than older children and adults . Infants younger than one year of age are particularly susceptible to this disease and are at the highest risk of death, 43% to 78% of mortalities from the illness among children less than 5 years of age occur in infants less than one year [13–15].
Although the number of children currently dying from diarrhea continues to be unacceptably high, it is substantially lower than the 5 million deaths estimated 20 years ago . The critical factors accounting for the reduction in mortality rates from this illness include widespread use of oral hydration solutions and the proper nutritional rehabilitation of sick infants .
The American Academy of Pediatrics has emphasized the importance of oral hydration and early nutritional support to aid these patients safely and effectively through the diarrheal episode . A rapid realimentation with age appropriated foods and an unrestricted diet is recommended, as soon as dehydration is corrected. Nursing should be continued for those infants being breast fed and a standard full strength formula to be given to those formula fed children. The old concept of "Bowel Rest" has no scientific validity and it can serve to aggravate and increase the risks of the disease . Apart from the undesirable metabolic effects of even brief fasts, withholding oral intake may further compound the intestinal absorptive processes and may lead to deterioration of the nutritional status of the patient . Even though feedings increase the stool output and diarrhea, children who are fed attain higher body weights at the end of the illness than children who are not fed. This was evident in this study. Patients who were fed juice as part of the nutritional intake during the diarrheal illness had a higher body weight at recovery than those fed water, although they exhibited larger stool losses during the first 24 hours of nutritional rehabilitation.
Diarrhea, like other infections, decreases the appetite and sick infants often reject most foods, although breast milk is better accepted . The lack of appetite may be mediated by interleukin 1, a hormone released by the white cells after infection . The intensity of anorexia may not necessarily correlate with the severity of the illness. A child may lose his or her appetite with even mild diarrhea, with anorexia lasting from a few hours to several days . As much as 20% to 70% of food available may be wasted or not eaten, during bouts of diarrhea . Thus feedings of a well accepted available energy source might be desirable and necessary to enhance the nutrient intake of sick infants and young children. The patients in this study readily consumed fruit juice, and the intake of this food did not displace the consumption of other nutrients. Juice feedings resulted in a higher energy balance, particularly among the infants fed WGJ. Infants fed juice ingested 14–17% more calories than those given WA, AJ and WGJ ingested 95 and 98 calories/kg/d respectively, whereas those receiving WA consumed 81 calories/kg/d.
Previous data showed that fruit juices differ in carbohydrate composition and that juices containing equimolar concentrations of glucose and fructose were best absorbed throughout the first 5 years of life [7, 23]. Similarly we have previously shown that this type of juice is better tolerated after recovery from acute diarrhea . The present study confirmed that this juice was better suited during the acute stages of the illness. The fecal losses associated with consumption of WGJ juice during the treatment of acute diarrhea were lower than those observed during feedings of juice containing higher fructose to glucose ratios and sorbitol. However, the stool output was highest only during the first day of treatment, with differences in stool output rapidly disappearing with recovery from the illness. All patients improved within 3–4 days while ingesting juice and none of them developed persistent diarrhea. The ability to tolerate carbohydrates was also similar among the 3 groups of patients.
The patients were given ad libitum up to 15 ml/kg/dose of juice twice daily throughout the study. This dose of juice exceeded the recommended allowance by the AAP-CON  which limits the intake of juice to one serving of 4–6 oz per day to children of this age. However by allowing the patients to ingest at will the high energy drink during the illness, they did not consume the full amount of juice offered, they only ingested approximately 17 to 21 ml/kg/day, those receiving WA consuming the lesser amounts. The patients given juice feedings also ingested more fluids. One can speculate that fluid intake was higher due to fecal losses replacement and/or thirst induced by juice. A covariance analysis and a robust regression to determine a possible confounding factor did not support that possibility. No differences were found among groups by adjusting the stool output to ORS or fluid intake. However, the ORS volume represented the most important fluid intake, indicating that diarrhea duration and stool losses were the consequence of this finding.
The maintenance of a positive energy balance during the illness may be of particular importance for the vulnerable infant who is at a higher nutritional risk even before developing diarrhea [19, 22]. This illness is considered to be one of the most important risks for the development of malnutrition . Diarrhea and other infections affect the body's economy through a number of mechanisms including the decreased absorption of nutrients [22, 24, 25]. The provision of simple carbohydrates in a balanced proportion, as present in some juices, may facilitate energy balance even during the illness and may be positive for the infant's nutritional rehabilitation . The ingestion of juice during the acute episode of diarrhea provided a higher average energy intake than that of those fed WA (+ 12 cal/kg/day for AJ and 18 cal/kg/day for WGJ). However ingestion of larger amounts of fruit juice has been associated with prolongation of diarrhea . Additionally ingestion of juices containing high fructose and sorbitol may also be associated with other negative consequences, i.e. colic  and increased energy requirements .
The transient malabsorption during the acute phase of the illness may be overcome by absorptive advantages of the carbohydrate composition of specific feedings . Similar results were found with amino-acid based ORS  and with the low-osmolality ORS [16, 29, 30], though there was a negative role of high osmolality solutions. However the most important therapy for the sick infant is the rapid rehydration, the maintenance of fluid and electrolyte balance and the provision of adequate feedings.