American Journal of Clinical Nutrition, Vol 9, 596-605, Copyright © 1961 by The American Society for Clinical Nutrition, Inc.

An Interracial Study on the Serum Protein Pattern of Adult Men in Southern Africa

¹ From the Department of Medicine, University of Cape Town, Cape Town, South Africa

In 1952 using filter paper electrophoresis the serum protein pattern of European subjects was compared with that of Bantu. The outstanding differences were a lower serum albumin level and higher gamma globulin level in the Bantu. These differences could be reduced by excluding Bantu from a tropical environment or by excluding Bantu from a similar nontropical environment but with elevation of the erythrocyte sedimentation rate. Serum protein patterns were similar in Bantu and Bushmen living in the same tropical environment.

In 1955 the interracial survey was repeated but a sample of Cape Colored subjects was included. Similar interracial differences were found and the Cape Colored subjects, intermediate in the socioeconomic scale, possessed a protein pattern intermediate between that of Bantu and European subjects, particularly with respect to the globulin values.

Within each ethnic group the serum albumin level decreased in magnitude and the serum gamma globulin level increased in magnitude with advancing age.

Subdivisions of each ethnic group into two income categories revealed that the serum gamma globulin level was higher in the low income group while, with the exception of the European, the serum albumin level was lower in the low income group.

Regression analysis revealed a highly significant association between serum albumin level and dietary protein intake in that serum albumin levels increased as protein intake increased, but only up to a certain level. Above that level of protein intake no further rise in the serum albumin concentration occurred.

An inverse relationship existed between the serum albumin and gamma globulin levels, but evidence was presented that factors other than dietary protein intake influenced the level of gamma globulin in the serum.