This article aims at examining the link between the changes in diverse food and medicinal plants and the changing population patterns in Western Kenya region. The paper involved a comparative approach in a regional landscape (from Luhya, Luo and Gussi). The study employed desktop research approach, entailing careful study and analysis of published literature. Food and medicinal plants were identified by their origins, whether local or exotic. The paper as established database of plants used as food and medicine by communities in Western Kenya, the Easter part of Great Lakes Region (GLR) .