[Investigation and analysis of salt sales and public consumption in supermarkets in Tianjin after salt reform].

OBJECTIVE

To investigate the consumption status of iodized and iodine-free salt and the attitude and reasons for Tianjin residents to choose salt after the reformation of the salt industry systems, and to provide a scientific basis for iodine supplementation and protect the public iodine adequate.

METHODS

Stratified sampling method was used to investigate supermarkets of different sizes in 16 districts of Tianjin from December 2017 to May 2018. And 4-8 different sizes supermarkets were selected in the east, south, west, north, and middle directions of each district, and 25 consumers were selected in each district to conduct a questionnaire survey by Population Proportionate Sampling(PPS). Questionnaire survey was used by investigators to ask and record the respondents age, gender, salt type, time to eat a bag of salt, number of people dining, frequency of seafood consumption, special populations in the family(children, pregnant women or lactating women), reasons for choosing iodized salt or iodine-free salt. And the supermarket sales staff were questioned on the type and proportion of salt sold, the monthly sales of iodized salt and non-iodized salt, and the trend of sales volume.

RESULTS

The sales volume of iodized salt was significantly greater than that of noniodized salt in the 94 different supermarkets(P<0. 05). Supermarkets with a rise in sales volume of non-iodized salt and iodized salt accounted for 40. 0% and 32. 9%, respectively. Significance difference was found in the prevalence of thyroid disease among people with different salt selection types(χ2= 15. 052, P<0. 05). The prevalence of thyroid disease is higher in the non-iodized salt group. No significant difference was found in the prevalence of thyroid disease between different genders and age groups(χ2= 0. 937, P > 0. 05; χ~2=2. 442, P > 0. 05). From the reasons why consumers choose different types of salt, the choice of iodized salt in the population, habits(45. 0%) accounted for a larger proportion, the prevention of thyroid disease accounted for 49. 6%. Among the people who chose to have no iodized salt, it is considered that Tianjin is a seaside city that does not need iodine supplementation, accounting for 55. 9%, and those who prevent thyroid disease account for 35. 6%. Prevention of thyroid disease account for 46. 9% and those who do not need iodine supplementation account for 40. 0% in a mixed population.

CONCLUSION

There are blindness and misunderstanding when consumers select the type of salt.