It is becoming increasingly evident that not all people respond equally to diet. Nutrigenetics and nutrigenomics is the study of how genes affect dietary response or how nutrients affect gene expression. Understanding gene–nutrient interactions has become essential in many areas of study to account for variation in results. Identifying subgroups or individuals who might benefit from more targeted recommendations has also been a result of studying these interactions. This review summarizes findings from genetic polymorphisms in apolipoprotein E, fatty acid desaturase, lipoxygenase-5, peroxisome proliferator-activated receptors, apolipoprotein A1, apolipoprotein A2, apolipoprotein A5, and methylenetetrahydrofolate reductase associated with cardiovascular disease.