Malabsorption Following a Brief Fast

Abstract

Purpose: Diarrheal diseases are considered an important inducers of malnutrition because they affect nutrition through a number of mechanisms; (1) reduced food intake, (2) altered digestion and absorption, (3) impaired utilization of nutrients, (4) other metabolic alterations. During the initial treatment for acute diarrhea, patients are fasted for 24 to 72 hours to provide rest for the gastrointestinal tract. A routine progressive diet, beginning with a clear-liquid diet, is a frequent diet order. However, there are no scientific data to support the use of clear-liquid diets following a brief fast. We investigated malabsorption in patients with acute infectious entero-colitis who were fasted for a few days. Methods: Studies were performed in 22 patients (mean age 38 years, male/female = 13/9). Their diseases diagnosed were acute entero-colitis in 16 patients, colonic diverticulitis in 5, and osteoarthritis in 1. Patients are fasted during the initial treatment. The mean duration of fasting was 2.7 days (1–6). Diets began with mechanical soft diets in 18 patients, full-liquid diets in 3, solid foods in 1 (osteoarthritis). They all were asked to inflate a breath-collecting bag before taking breakfast, lunch, and dinner. Breath hydrogen concentrations were measured by using breath analyzer and compared to the fasting values. Results: Breath hydrogen concentrations before meals varied from 0 to 12ppm. An increase in breath hydrogen concentration after the beginning of serving meals was found in 20 of 22 patients (91%), with a mean value of 17.4ppm (1–53). Ten patients (46%) had an increase of more than 10ppm, 24 to 36 hours after meals. No abdominal symptom was developed despite of a frequent increase in breath hydrogen concentration. Although diets progressed gradually to a common solid foods as tolerated, breath hydrogen concentrations were decreased to the baseline a several days after serving meals. There were no significant differences among three kinds of diets. Conclusions: Malabsorption following a brief fast was detected more frequently than expected in the present study. Apart from the undesirable metabolic effects of even a brief fast, withholding oral intake may alter intestinal absorption.