DIGESTION AND ABSORPTION OF SORBITOL, MALTITOL AND ISOMALT FROM THE SMALL-BOWEL - A STUDY IN ILEOSTOMY SUBJECTS

Objective: To quantify small bowel digestion and absorption of sorbito l, isomalt and maltitol in ileostomy patients and estimate the metabol izable energy. Subjects: Study A: Nine ileostomy patients, under a con stant controlled diet, ate during three consecutive days 2 milk chocol ate bars per day, containing 2 x 15 g of polyol, each day with another polyol in random order. The first bar was taken 30 min after breakfas t, and the second bar, 7 h after breakfast. Effluents were recovered d uring the whole study. Study B: 5, 10 or 20 g of sorbitol or isomalt w ere consumed each day in a drink during two 3-day periods by two ileos tomy subjects. The recovery in the ileal effluent was measured over 24 h. Results: Study A: Carbohydrate recovery in ileostomy effluent was 26.8 +/- 2.8% (mean + SEM) for sorbitol, 24.8 + 5.7% for maltitol (2/3 as sorbitol) and 40.0 +/- 0.7% for isomalt (1/3 being sorbitol and ma nnitol). Ileal excretion, compared with a day without polyol, was comp ared in 4 subjects. The total volume excreted, as well as dry matter i ncreased after polyol consumption. When taking this extra loss into ac count, the metabolizable energy value of the polyols for 2 x 15 g inta ke were: sorbitol, 12 kJ/g (2.8 kcal/g); maltitol, 13 kJ/g (3.1 kcal/g ); isomalt, 9 kJ/g (2.1 kcal/g). Study B: The level of digestion and a bsorption of both sugar alcohols was dose dependent. Conclusions: Thes e results indicate that sorbitol, maltitol and isomalt are rather exte nsively absorbed, but the digestibility of the other nutrients is also reduced, due to the osmotic load caused by the polyols in the small i ntenstine. There are evidences of a dose dependency of the energy valu e of the polyols.