Zinc Nutritional Status and Risk Factors of Elderly in the China Adult Chronic Disease and Nutrition Surveillance 2015

Objectives: To analyze the serum zinc nutrition status of the Chinese elderly, and to assess the risk factor for zinc deficiency. Methods: 3727 elderly people over 60 years old were randomly selected from 302 monitoring points in 31 provinces of China Adult Chronic Disease and Nutrition Surveillance (CACDNS) 2015. Blood samples were selected from the biological sample bank of CACDNS 2015 and the basic information were collected by questionnaires. The criteria of serum zinc deficiency recommended by the International Zinc Nutrition Consulting Group (IZiNCG) were adopted, and the related factors were also analyzed. Results: The median serum zinc concentration of Chinese elderly was 99.2 (84.3~118.7) μg/dL. The overall adjusted prevalence of zinc deficiency was 8.68%, with a 95% confidence interval (CI) of 7.74% and 9.61%. Significant differences were found in different sex, age groups, Body Mass Index (BMI), residence region, race and education level in terms of serum zinc status in the elderly (p < 0.05). Participants who are males, aged above 70y, with BMIs of less than 18.5 kg/m², living in rural areas, minority, and with the lowest income had a higher prevalence of zinc deficiency in the subgroups under different classifications. The risk of zinc deficiency in the elderly over 70y was 1.44 higher than those aged 60–69y (OR = 1.44, 95%CI 1.14–1.82), and the minority elderly has a 1.39 higher risk than Han nationality (OR = 1.39, 95%CI 1.01–1.91), while overweight/obesity and female elderly were at lower risk (OR < 1, p < 0.05). Conclusions: The overall prevalence of zinc deficiency in the elderly was highest in all adults in the CACDNS. It is recommended that the male elderly, over 70 years, and the minority elderly should pay more attention to the zinc nutrition status of their own.