Introduction: Zinc as an antioxidant can attenuate the effects of ionizing radiation. Contrary to theoretical radiobiological concepts, studies have pointed to the differential effects of zinc on normal and tumor cells, respectively. Therefore the present study was conducted to highlight the effects of zinc supplementation on adverse events and response rates of head and neck cancer patients who had undergone definitive concurrent chemo-radiotherapy (CCRT). Materials and Methods: Case records of patients with head and neck cancer who underwent definitive chemo‑RT were analyzed from July 2015 to July 2018. Those who received zinc supplements were categorized as Arm A and those who did not as Arm B. All patients received a total of 6600–7000 cGray RT with weekly cisplatinum. Radiation Morbidity Scoring System was used to summarize data on adverse events. Computed tomogram scans were compared for documenting response rates. Results: Data were collected from 95 patients under Arm A and 107 in Arm B. 15.8% in Arm A and 21.5% in Arm B had RT interrupted for >1 week. Although the results were not statistically different for > Grade 2 toxicities, patients in Arm A fared better than those in Arm B. Interestingly, when the two groups were analyzed for salivary gland adverse events, 74 patients in Arm B complained of ≥ Grade 2 toxicities as compared to 37 in Arm A, the results being statistically significant (P = 0.000017). Overall, response rates were 88.4% in Arm A and 92% in Arm B. Conclusions: Zinc supplementation lends some of its radioprotective effects in normal tissues with salivary glands deriving the major benefits.