Objective To evaluate the effect of nutritional intervention on the nutritional status of patients with upper gastrointestinal cancer before and after chemotherapy. MethodsAdvanced upper gastrointestinal cancer patients (n=82) were screened and assessed by NRS 2002 and PG-SGA. According to the results of PG-SGA, the patients were divided into three groups: well-nourished (A), moderately malnourished or suspected of being malnourished (B) and severely malnourished (C). Nutritional intervention is based on the "five steps of malnutrition". Nutritional status, weight, energy and protein intakes of the patients were compared before and after chemotherapy. ResultsBefore intervention well-nourished patient was 10.98%(8/82), moderately malnourished or suspected of being malnourished was 50.00%(41/82), severely malnourished was 39.02%(32/82). The incidence of nutritional risk and malnutrition after intervention decreased, before intervention was 52.44% and 89.02% respectively, after intervention was 35.37% and 75.61% respectively. Compared to before chemotherapy, the weight of patients in well-nourished group and moderately malnourished or suspected of being malnourished group maintained stability, [(67.88±11.25) kg vs (67.22±10.17) kg, P>0.05 and (63.00±11.50) kg vs (62.58±11.48) kg, P>0.05], respectively. While in severely malnourished group, weight loss significantly [(59.92±9.61) kg vs (59.15±9.46) kg, P<0.05]. The average daily dietary intake of energy and protein increased significantly of moderately malnourished or suspected of being malnourished group and severely malnourished group, compared to before intervention (P<0.05) well-nourished group maintained stability (P>0.05). ConclusionsNutritional intervention can reduce the incidence of nutritional risk and malnutrition of patients with advanced upper gastrointestinal cancer, decrease weight loss, improve nutritional status, and may help to improve the clinical outcome.