Many clinical conditions exist in which it is desirable to stimulate or suppress the immune system, and many different drugs are able to do this. It is also well known that nutrition may affect human health and immune responses. Nutritional factors are crucial components of the diet and essential for normal growth and development of both vertebrate and invertebrate organisms. Many of these components have been shown to play different roles in the immune response and, under different circumstances, they can significantly modulate the immune system to create an effective response. Diet and its components are known to play an important factor in the process of inflammation and in turn on the health effects related to inflammation, such as cancer and cardiovascular diseases. Previous research so far has mainly looked at the effect of specific food stuffs or nutrients on inflammation and health outcomes. The aims of the present review was a) to underline the fact that diet as a whole plays an important role in modifying inflammation and health outcomes related to inflammation, aging, and colon cancer; b) to show the in vitro cytotoxic effect of LipoFishins (E-Congerine 10423®; AntiGan™) obtained from the Atlantic Conger conger marine organism present on the Galician coast, against different human tumor cell lines; c) to show the in vivo effect of E-Congerine-10423® on colonic inflammation induced in mice by seven weeks' exposure to 2% of dextran sulfate sodium (DSS); and d) to show the effect of E-Congerine-10423® (AntiGan™) on tumor markers (TMs) in healthy subjects and in patients with different types of cancer at the time of diagnosis. Preliminary data in a limited number of cases indicate that about 50% of the patients show a reduction in the levels of tumor markers (TM), and this response was much more evident in patients with cancer, when TM values are above normal range. Finally, all the above mentioned results suggest that diet has a major role in controlling inflammation and thereby plays an important role in the development or prevention of various chronic diseases, hence public health steps should be taken to modify the individual's whole diet and to promote the intake of specific natural compounds.