Increase in serum zinc levels after supplementation of zinc deficient nursing home elderly

Abstract

Pneumonia is among the leading causes of morbidity and mortality in elderly. Zinc deficiency is associated with reduced immunity. Previously we showed that 30% of nursing home elderly (NHE) had low serum zinc levels, and zinc deficiency was significantly associated with higher incidence and duration of pneumonia. We conducted a randomized, double‐blind, placebo‐controlled study to determine if supplementing NHE with 30 mg/d of zinc for 3 months increases serum zinc levels. Participants (≥65 years) had serum zinc levels < 70 μg/dL, albumin > 3.0 g/dL, BMI > 18 kg/m2, and no preexisting conditions such as lung neoplastic disease. Participants were randomized into a zinc (30 mg/d zinc) or placebo (5 mg/d zinc) group; capsules also contained 1/2 DRIs of essential nutrients. Serum zinc, albumin, CRP, and copper levels were determined before and after supplementation. Using t‐test, the mean(±SD) serum zinc difference (baseline to month 3) is significantly higher by v17(±9) μg/dL in the zinc versus placebo group (p=0.004). The control group had a decrease of 7(±8) μg/dL, while the zinc group had an increase of 10(±10) μg/dL. No statistically significant changes in albumin, copper, or CRP levels were detected; correcting for these parameters did not impact zinc levels. Supplementation of zinc deficient NHE with 30 mg/day of zinc for 3 months increases serum zinc levels. Future studies are needed to determine if zinc supplementation can reduce incidence and duration of pneumonia in NHE. Supported by USDA (58‐1950‐7‐707)