Dietary nutrition and nutrients associated with one carbon unit metabolism among Kazakh people in areas with high esophageal cancer incidence in Xinjiang

Objective To investigate dietary nutrition and intakes of nutrients associated with one carbon unit metabolism among Kazakh residents in Toli county,an area with high esophageal cancer incidence,in Xinjiang Uygur Autonomous Region (Xinjiang) and to provide a basis for conducting health education on nutrition knowledge and esophageal cancer prevention in the population.Methods With stratified random cluster sampling,a face-to-face questionnaire survey on demography and daily diet during the previous one year was conducted among 244 Kazak residents aged ≥45 years and living in local areas at least for 5 years in Toli county of Xinjinag during June 2015;blood samples were collected among the residents for detections of serum folic acid and vitamin B₁₂ with automated chemiluminescence immunoassay.Results Compared to those recommended in dietary guidelines of Chinese Nutrition Society,the residents reported higher average per capita daily intakes of cereals and potatoes (499 g),meats (315 g),and milk (359 g),lower intakes of fruits (128 g),eggs (14 g),beans (5 g),and fish and shrimp (0 g),and adequate intake of vegetables (399 g),respectively.For the residents,the calculated daily intake of protein,cholesterol,and vitamin A were 104.00±20.63 g,383.63±130.64 mg,and 1175.24±260.74 μg retinol equivalent (RE),accounting for 160.00%,128.00%,and 147.00% of the dietary reference intakes (DRIs);the average daily intakes of thiamine (0.83±0.14 mg) and vitamin E (10.13±2.28 mg) were 59.29% and 72.35% of the DRIs;and the intakes of vitamin B6 (0.47±0.11 mg) and folic acid (45.46±14.62 μg) were only 29.38% and 11.37% of the DRIs.The content of serum folic acid was 8.09±3.85 nmol/L and lower than the reference value (13.4 nmol/L),while the serum vitamin B₁₂ was 296.55±133.99 pmol/L and within the range of reference (133-675 pmol/L).Conclusion The dietary structure is unreasonable for the adult Kazakh local residents in the area with high esophageal cancer incidence in Xinjiang and the intakes of beans,fish and shrimp,fresh fruits,and green leafy vegetables should be increased for supplements of some inadequate nutrient intakes,particularly for vitamin B6 and folic acid among the residents.