Restriction of protein or energy intake during gestation or early life is linked to developmental defects in the endocrine pancreas and insulin resistance. Aims: To study whether a saturated fatty acid-rich diet during gestation and/or after the weaning period may be detrimental to the insulin secretory capacity later in life. Study Design: Female Wistar rats were fed diets rich in carbohydrate (CHO) or saturated fat (SAFA) during pregnancy. The male offspring were split into five subgroups: after birth group 1 (control) continued on CHO and group 3 on SAFA. Group 2 continued on the CHO diet during the nursing period but changed to SAFA post weaning. Group 4 continued on SAFA, but changed to CHO post weaning. For group 5 the offspring of mothers given a SAFA diet were changed to nursing mothers on a CHO diet immediately after birth, and continued on the same diet post weaning. After 14 wk, the islets of Langerhans were isolated for determination of insulin secretory capacity in static incubation and dynamic perifusion experiments. Results: We found a negative correlation (Coef: - 3.1, 95% CI: -6.1 to -0.0, p < 0.05) between a diet rich in saturated fat fed to mothers during gestation and a positive correlation (Coef: 4.4, 95% CI: 0.9 to 7.8, p = 0.01) between nursing mothers’ diet and the capability to secrete insulin in the offspring. Conclusion: Our results indicate the importance of applying a nutrient-balanced diet during pregnancy and the nursing period on the later insulin secretory capacity in the offspring.