China National Nutrition and Health Survey 2010â2013(CHNNS2010â2013) is a nationally representative cross-sectional study. Data for the present analysis were taken from 34 large cites and 41 small to medium cities of CNNHS 2010â2013. Serum samples were collected from the aged who were older than 60 years old and had finish the diet survey.
2159 serum 25(OH)D levels were measured by an radioimmunoassay kit (DiaSorin 25-Hydroxyvitamin D 125I RIA), 947 serum parathyroid hormone levels were measured by ELSA-PTH radioimmunoassay kit.
Over 30% of Chinese old people were vitamin D deficiency, and this rate was much higher in women than men. Serum parathyroid hormone levels from the large cites were higer than from small to medium cities, both for male and female. There wasnât any correlativity between serum 25(OH)D and parathyroid hormone levels. Not using vitamin D supplementation and residing in areas with low ambient UVB levels increases the risk of vitamin D deficiency, especially for eldly women.
Vitamin D deficiency is prevalent among the Chinese old people.