Nutrition support during cancer therapy is considered to be a new field of research. The way forward during cancer therapy includes many studies in several fields. The gut microbiota seems to interfere with several cytotoxic agents influencing their action, effectiveness and toxicity. Curcumin inhibits COX-2 and NF-kB in cancer cells competing the action of irinotecan and cyclophosphamide. Other nutrients of research are green tea, omega – 3 fatty acids, melatonin and several herbs. Fasting Is characterized by the complete deprivation of food but not water, with intervention periods of normal food intake, whereas Intermittent fasting, Periodic fasting, Short term fasting, Fasting mimicking diet, or combination of fasting diets have been used in several clinical trials. The results revealed improvement of the chemotherapeutic response and in combination with cytotoxic agents elicited differential responses in normal and cancer cell, a phenomenon known as differential stress resistance (DSR). Ketogenic diets have been used in clinical trials alone or in combination with fasting diets. Though they seem to be well tolerated no significant results were documented. The path forward for harnessing new dietary approaches in oncology seems to be oriented towards a personalized dietary approach guided by certified dietitians.