Objectives To determine whether deterioration of dental condition at the outset of management of head and neck cancer (HNC) is a nutritional risk and whether social deprivation is a cause of the poor dental condition observed in HNC patients. Material and methods A nutritional assessment form (NAF) and the Nutrition Risk Index (NRI) were used to standardize the nutritional status of 108 patients at the outset of management of HNC (2017-2019). The NAF includes assessment of weight loss over the past 3 months, the amount and difficulty of food intake, and the presence of digestive disorders. Dental condition was assessed by the decayed, filled, and missing teeth acopre (DFM) index and the masticatory coefficient (MC). Dental status and social deprivation were correlated with the EPICES score. Results A correlation was found between the extent of weight loss and dental condition. The MC was higher in absence of weight loss (46% vs. 27%, p = 0.03) and the DMF lower when weight loss was less than 5% (22.3 vs. 26.9 if > 5% loss of weight, p = 0.005). No correlation was found between dental status and nutritional status. Social deprivation was associated with a lower MC (26% vs. 50%, p < 0.001). Conclusion Dental condition is a risk factor for weight loss at the outset of management of HNC but is not a determinant of nutritional status. Clinical relevance Dental condition is no longer considered simply as a source of potential complications after radiotherapy but also as an important factor for nutritional status.