The efficacy of a moderate amount (7 grams) of apple pectin in diminishing post-prandial insulin needs in insulin dependent diabetics (IDD) has been tested using an artificial pancreas in a sequential analysis. With this method, only four patients who served as their own control, showed significant reductions in insulin requirement of 3 Iu with pectin after a 60 g carbohydrate mixed meal. The use of pectin cut by 35 per cent the post prandial insulin demand. The patients judged the treatment as acceptable. More prolonged use in IDD is advisable.