Dietary Survey Of High Phosphate Intake And Its Inhibitive Effects On The Immune System Of The Body

ObjectiveDietary survey suggested that the proportion of children's calcium and phosphorus intake was abnormal,and the average of phosphorus intake of infant was twice as much as that of RNI value,while calcium intake was less than half of RNI value.The phosphorus uptake mentioned above is based on the organic phosphorus content calculated by the nutrition survey software.The survey indicated that children are keen on meat and snacks which are quite often added inorganic phosphate during processing to obtain the desired taste and flavor.So far,there is no legislation requiring pre-packaged foods to be labeled with the amount of inorganic phosphorus additives,and the total amount of phosphorus intake from food remains uncertain.The test conducted determination of total phosphorus content of food samples according to national standard of China,intending to figure out the total content of phosphorus in certain food as well as the usage of Inorganic phosphate-typed food additives.Used widely in food processing,Inorganic phosphate-typed food additives are related to human health.Therefore,it is essential to study the effect of long-term feeding of high-dose inorganic phosphorus diet on the human body,especially the immune system.Methods(1)The dietary survey was carried out by 24 hours review and weighing method.The data were analyzed by the software of nutritional calculator and SPSS.The results of the analysis were used to evaluate the dietary structure and intake of various nutrients,and to understand the average phosphorus intake of preschool children.(2)Use acid to dissolve food samples,the digestible solution of samples was tested by the method of hydroquinone and sodium sulfite reduction.Spectrophotometer is used to determine the photometric value of molybdenum at the wavelength of 660 nm,and total phosphorus content of samples was calculated based on phosphorus standard curve.(3)A high inorganic phosphorus intake model was established.At the end of the experiment,acute inflammation in mice was stimulated by lipopolysaccharide(LPS),test the serum phosphorus detection,tumor destruction factor(TNF-?),Flow cytometry was used to detect the use of macrophage typing and transcriptional analysis were used to analyze the uptake of high inorganic phosphorus in mice.Changes in the immune system occur when the body is exposed to acute inflammation.Results(1)The results of dietary survey show that: the preschool children in kindergarten would like to eat meat and they don't like milk.The intake of children nutrient elements is not reasonable,such as folic acid,calcium,phosphorus,copper,iodine and other elements have a large gap with the intake of RNI.Intake of children the proportion of Ca:P are different from the reasonable level.The amount of phosphorus is two times more than the RNI value.(2)Some food sold in the market was generally high.The phosphorus content of canned luncheon meat is 3 263.2 mg/kg,phosphorus content of sausage is 3078.5mg/kg,the phosphorus content of wafer is 2 106.3 mg/kg,the phosphorus content of instant noodles was2 410.6 mg/kg and chocolate was 3 966.5 mg/kg.(3)Animal test results: the concentration of orthophosphate gavage was positively correlated with the concentration of serum total phosphorus;orthophosphate significantly inhibited the secretion of tumor necrosis factor(TNF-?)induced by LPS;gavage phosphate changed the polarization type of peritoneal macrophages in mice,and the concentration of gavage was positively correlated with the ratio of M2/M1;the expression of CXCL9,CXCL10,CXCL11 and STAT 1 decreased.Conclusion(1)The preschool children'diet structure is unreasonable and their nutrient intake is not equal.Parents and kindergarten administrators should correct their children's bad eating habits in time.(2)The meat,biscuits and instant noodles in the market contain high total phosphorus content,people who often eat this kind of food may be in the state of high phosphorus intake for a long time.(3)Animal experiments show that high inorganic phosphate intake can reduce the expression of CXCL9,CXCL10 and CXCL11 genes,thus inhibit the type of M1 type macrophage and cause the decrease of tumor necrosis factor secretion in mice.This change may lead to the decrease of anti-tumor immunity of the body,and accelerate the proliferation and proliferation of tumor.