The effects of aspartame on mast cells and basophils

The artificial sweetener aspartame was studied to determine whether it had any direct effects on mast cells and basophils. Aspartame was not shown to be a direct mast cell or basophil secretagogue in vitro, or in vivo as assessed by skin testing. During an acute incubation, aspartame did not affect IgE-mediated histamine release from mast cells. However, mast cells cultured in aspartame for periods of up to 9 days showed enhanced rates of proliferation and decreased responsiveness to releasing stimuli. The effect of aspartame on proliferation of cells in culture could be ascribed to a non-specific enhancing effect of its constituent amino acids.