Abstract: Objective To evaluate the effect of comprehensive intervention in reducing salt,oil and sugar（"three reductions"） for residents in Nanjing City,so as to provide scientific basis for formulating the "three reductions" strategy. Methods A multistage cluster random sampling method was used to select 240 households from 8 districts of Nanjing City in 2021,and the family members aged ≥2 years were selected as the subjects for the "three reductions" comprehensive intervention,which lasted for 6 months. The "three reductions" knowledge and behavior of the subjects aged ≥12 years old were investigated by questionnaire,and the intake of cooking salt,cooking oil and cooking sugar was investigated by using 24-hour weighing method for 3 consecutive days before and after the intervention. Results A total of 229 families with complete data were included in the analysis. After intervention,the per standard person day intake of cooking salt[M（P₂₅,P₇₅）] was 7.63（4.96,12.00）g,which was lower than before intervention,which was 10.18（6.44,16.37）g. The per standard person day intake of cooking oil was 28.9（513.06,48.99）g,which was lower than before intervention,which was 32.75（20.46,53.82）g. The per standard person day intake of cooking sugar was 3.02（0.00,6.73）g,which was higher than before intervention,which was 2.47（0.00,5.93）g. There were significant differences in the intake of cooking salt,cooking oil and cooking sugar per standard person-day before and after the intervention（all P<0.05）. Totally 461 respondents aged ≥12 years old were included in the survey,and it was found that the scores of "three reductions" knowledge of different groups of people,such as gender,age group and education level,after intervention were higher than before intervention,and the differences were statistically significant（all P<0.05）. In addition to 12-<18 years old group and primary school education and below,the "three reductions" behavior scores of the other groups were higher after intervention than before intervention,and the differences were statistically significant（all P<0.05）. After the intervention,the survey subjects' awareness of salt and edible oil intake standards and the hazards of high salt,oil and sugar was higher than that before the intervention,and their adherence to salt limiting spoon and oil control pot was higher than that before the intervention,and the behavior of eating preserved products and frying and baking food was improved than that before the intervention,with statistical significance（all P<0.05）. Conclusion "Three reductions" comprehensive intervention can effectively improve the awareness rate of salt,oil,and sugar related knowledge among residents,and reduce the intake of cooking salt and cooking oil. However,in the follow-up "three reductions" intervention work,we should focus on increasing intervention efforts to reduce oil and sugar while emphasizing salt reduction,promoting the formation of good dietary habits of residents.

Key words: Salt reduction, Oil reduction, Sugar reduction, Intervention, Effect evaluation