Low fasting blood sugar levels and insulin sensitivity have been consistently reported in Africans. To study the role played by insulin and growth hormone (HGH) in the genesis of this state, plasma insulin and HGH levels were measured in 40 healthy fasting Africans. Mean plasma insulin and HGH were 10.7 +/- 1.3 muU/ml and less than 1 muU/ml respectively. These are in the same range reported for Caucasians in the literature. The response of plasma insulin and HGH to a menal was further studied in 80 healthy Africans. While insulin response was brisk and adequate, the HGH response was rather sluggish. The significance of these findings is discussed.