In seven type II (non-insulin-dependent) diabetic patients, given either 50 g glucose or a mixed meal potentially containing 61 g glucose as starch and sucrose, the postmeal plasma glucose area integrated over 4 h was less after the mixed meal. The insulin area was considerably greater (2.1-fold). The greater increase in insulin could be explained largely, but not entirely, by the protein and fructose in the mixed meal (85%) which, in addition to glucose, are known insulin secretagogues. The residual unexplained increase may be due to a synergistic interaction of these secretagogues, an unidentified insulin secretagogue, or by a reduced insulin removal rate. These possibilities remain to be explored.