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It has been hypothesized that micronutrient levels of - amongst others zinc - play a role in the immune response to vaccination. It is also hypothesized that decreasing levels of nutrients would be associated with decreased responses to influenza vaccination. The purpose of a recent study was to determine whether serum zinc levels are associated with influenza vaccine response in adults 65 years or older. Participants in this study included 205 adults 65 years or older who received a influenza vaccine and donated blood samples before and 21 to 28 days after vaccination. Of these, 20% had low serum zinc levels.
After adjusting for age, sex, body mass index, and prevaccination titer., the study showed no association between variations in levels of zinc and influenza vaccine response.
Our advice remains: eat healthy and vaccinate yourself against seasonal influenza.
 Sundaram et al: Vitamin E, vitamin A, and zinc status are not related to serologic response to influenza vaccine in older adults: an observational prospective cohort study in Nutrition Research - 2014