ETHNIC IMMUNITY TO CORONARY HEART-DISEASE

Dietary fat intake is often regarded as a major determinant of coronary heart disease (CHD) rate and it has been deemed unnecessary to invoke racial or other factors to explain the differences in CHD rates among different ethnic groups. Despite a high prevalence of CHD risk factors such as hypertension, obesity, and smoking, CHD remains a rarity in westernized black Africans. Cord blood total cholesterol (TC), low density lipoprotein cholesterol (LDLC) and apolipoprotein B (apo B) levels were measured and found to be respectively 12.1%, 18.3% and 22.4% lower in black neonates when compared to white neonates. These differences were again studied in a group of young black African males and a comparable group of age-matched whites who had been exposed to the same environment and western diet for at least 2 years. Although the body mass indices and serum albumin concentrations in the adult males were not significantly different, serum levels of TC, LDLC and apo B were 10.7%, 18.7% and 39.7% lower in the blacks, respectively. Furthermore, high density lipoprotein cholesterol (HDLC) and Apolipoprotein AI were 20.2% and 9.5% higher, homocysteine 45.6% lower and coagulation factor VII 26.6% lower in the adult black Africans. It is concluded that blacks are biochemically less responsive to an atherogenic diet than whites and these differences are already present at birth.