To the Editor:— Numerous investigators 1-4 have reported that the measurement of the urinary excretion of xylose after the oral administration of the sugar is a reliable means of testing the absorption of carbohydrates. Xylose is not metabolized by the body but is excreted unchanged in the urine. We used this test to establish whether patients with duodenal diverticula had demonstrable evidence of malabsorption. Serum carotene levels have also been found useful in screening patients from malabsorption. 3 Most of the individuals with duodenal diverticula were over 50 years old. None had diverticula of the ileum or jejunum. As we took data on these patients, we became aware that the lowest xylose excretion values were in the oldest patients. Texter 3 reports a decrease in xylose excretion after the sixth decade. However, our data were inadequate to allow statistical evaluation of our patient group. Methods and Materials:— Food was withheld