Immunosenescence via increased inflammatory cytokines may play key regulatory roles in facilitating cardiac infections and heart failure. Based upon recent evidence, we hypothesize that cytokine polarization due to aging directly dysregulates fibroblasts, leading to altered cardiac structure and dysfunction. Some dietary fatty acids should ameliorate heightened inflammatory cytokines thereby retarding cardiac pathology, loss of structural collagen and premature death from heart failure. For example, T-helper (Th) 2 cells' cytokine levels are very high in seniors who have increased heart disease due to suppressed resistance to cardiotrophic pathogens. In addition, such inflammatory cytokines deregulate fibroblasts, thus reducing collagen synthesis, weakening muscle structure and heart pump function for heart failure and hypertension. Therefore, supplementation with n-3 polyunsaturated fatty (PUFA) or conjugated linoleic acids, by reducing Th2 and increasing Th1 cytokines, may provide a sensible and widely available means to treat and even prevent excessive inflammatory cytokines and their cardiotoxic effects. On the other hand, dietary n-6 PUFA may promote cytokine polarization in seniors, exacerbating age-related heart dysfunction.