Recently, the investigators have been screening for anti-atherogenic or pro-atherogenic amino acids (AAs) in the macrophage model system to better understand their role in atherogenesis. The findings so far suggest that specific AAs induce selective anti-atherogenic effects (glycine, alanine, leucine and cysteine) or pro-atherogenic effects (glutamate and glutamine) in macrophages. Taking together the above previous reports with the mechanisms behind macrophage foam cell formation and atherogenesis, it is possible that AAs could be anti-atherogenic or pro-atherogenic via their mechanism of action on macrophage foam cell formation. This paradigm may serve as a basis for the development of novel cardio-protective, anti-atherogenic nutritional, or therapeutic approaches, that should be studied in human trials.