PurposeEating difficulty is a critical and common problem in head and neck cancer patients undergoing radiotherapy (RT). It leads to poor quality of life and extensive tube feeding use. Nutri-jelly, a food gel with semisolid texture, water-releasing ability, and ready-to-eat by spoon, was recently developed to alleviate the trouble. However, its efficacy was unknown. This study investigated the potential effect of Nutri-jelly on health-related quality of life (HRQOL) and nasogastric tube feeding use.MethodsA prospective quasi-randomized patients-preference controlled trial was conducted in 74 head and neck cancer patients. Subjects in study and control groups (37 each) had similar baseline HRQOL and body mass index and undergone definitive radiotherapy (25–35 RT fractions, 5,000–7,000 cGy). Only study group received a 200-ml box of Nutri-jelly as daily supplement throughout radiotherapy. HRQOL was scored by validated questionnaires. The use of tube feeding was collected from medical records.ResultsFrom 11 to 35 RT fractions, the study group maintained higher overall HRQOL score than that of control group (p < 0.0001). Multiple physiologic and psychological aspects of HRQOL especially swallowing difficulty and overall eating problems were significantly improved in study as compared to control group. Promisingly, the percentage of tube feeding use in study group (13.5 %) was dramatically lower than control group (48.6 %).ConclusionsContinuous supplementation of Nutri-jelly throughout radiotherapy may improve HRQOL and reduce tube feeding demand in head and neck cancer patients who preferred to take them. Nutri-jelly could be an alternative for head and neck cancer patients who have eating difficulty during radiotherapy.Electronic supplementary materialThe online version of this article (doi:10.1007/s00520-014-2488-5) contains supplementary material, which is available to authorized users.