Malnutrition is prevalent among oncology patients and can adversely affect clinical outcomes, prognosis, quality of life, and survival. This review evaluates current trends in the literature and reported evidence around the timing and impact of specific nutrition interventions in oncology patients undergoing active cancer treatment. Previous research studies (published 1 January 2010-1 April 2020) were identified and selected using predefined search strategy and selection criteria. In total, 15 articles met inclusion criteria and 12/15 articles provided an early nutrition intervention. Identified studies examined the impacts of nutrition interventions (nutrition counseling, oral nutrition supplements, or combination of both) on a variety of cancer diagnoses. Nutrition interventions were found to improve body weight and body mass index, nutrition status, protein and energy intake, quality of life, and response to cancer treatments. However, the impacts of nutrition interventions on body composition, functional status, complications, unplanned hospital readmissions, and mortality and survival were inconclusive, mainly due to the limited number of studies evaluating these outcomes. Early nutrition interventions were found to improve health and nutrition outcomes in oncology patients. Future research is needed to further evaluate the impacts of early nutrition interventions on patients' outcomes and explore the optimal duration and timing of nutrition interventions.