Growth factors

Cells take their growth and differentiation orders from a class of signalling proteins called growth factors, a family that includes epidermal growth factor, nerve growth factor, the insulin-like growth factors and fibroblast growth factor. Diet can nudge their blood levels: eating specific foods such as soy products shifts serum concentrations, with downstream consequences for bone metabolism and for the cellular changes involved in tumour development that scientists continue to investigate. For food researchers they are mainly analytical markers and bioactive components in functional-food studies, not ingredients added during manufacture.