Glycaemic & insulinaemic responses in men at rest following sago meal

Sago (Metroxylin sagu) is one of the main sources of native starch. In Malaysia sago dishes are commonly eaten with sugar. However, other societies use sago as a staple food item instead of rice or potato. The study was undertaken to investigate the effect of ingestion of different physical forms of sago supplementation on plasma glucose and plasma insulin responses, as compared to the white bread supplementation in man, during resting condition.

Twelve male subjects were given in random order with three different physical forms of a sago supplementation, viz., sago porridge (SR), sago paste (SP), sago gel (SG) and white bread (WB) which was repeated on separate days, at least, 1 wk apart after an overnight fast. Venous blood samples were collected at baseline and at 15, 30, 45, 60, 90, 120, 150 and 180 min after the start of each meal and were analyzed for plasma levels of glucose and insulin.

Plasma glucose reached peak at 45 min after supplementation of various sago meals. Plasma glucose area under the curve (AUC) for WB was significantly lower than SG but not significantly different from SR and SP. No significant difference was observed in plasma glucose AUC among the three sago meals. Plasma insulin AUC for SG was significantly higher than WB and SR. All three sago meals tested were not significantly different in their glycaemic responses. However, the insulin response was significantly lower for SR compared to SP and SG.

The present findings suggest that any one of the three sago meals tested in this study may be used to elucidate the effect of sago starch ingestion on exercise performance in the heat. Sago paste and sago porridge may be used for supplementation before and during exercise, whereas, sago gel may be used after endurance exercise during recovery process.