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Are fast food restaurants responsible for diabetes epidemic ? Instantaneous cut evidence from China. Estelle Zemmour . Objective. The first time this research is conducted
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Are fastfood restaurants responsible for diabetesepidemic?Instantaneouscutevidencefrom China. Estelle Zemmour.
Objective • The first time thisresearchisconducted • Benchmark papers:-Kaushal, « Do foodstamps cause obesity? Evidence from immigrant experience », Journal of HealthEconomics, 2007- Davis, Carpenter, « Proximity to Fast Food Restaurants to Schools and Adolescent Obesity », American Journal of Public Health, 2009. • Raises 3 main literaturereviews: 1) impact of diabetes on the economy2) impact of nutrition on diabetes3) impact of fastfood on obesity (used for methodology).
Someexplanations on Diabetes. • « Disease of the century »: touches rich over-nourished,aswell as under-nourished people.« Characterized by a disturbance in the use of sugar by the body due to a malfunction of the pancreas, whichdoes not release enoughinsulin in the body ». • International measure ( American DiabetesAsociation): Hba1c (measuresglycemic indexes over 3 pastmonths, thisis an average). -if higherthan 6,5 declared « diabetic » • 2 types: second one due to environmentalfactors: touches people after 40. Represents 95% of cases.
Measuring the main key variables for Nutrition • First index « Nutrition_1 »=Body Mass Index BMI=weight/(height²) • Second index « Nutrition_2 »= AverageGlycemic Index AGI= (total servings per day* carbohydrates content of food* glycemic index)/total carbohydrates content in diet (Salmeron and al, 1981)
Specification • 2 models: Nutrition_1Nutrition_2 linearregressionmodels probitmodels • Problems: reverse causalitysuspectedbetween the index of Nutrition and Diabetes • Proposed solution: instrumental variable approach.
Linearregressionmodels • 1rst model: Diabetes= a + b*Nutrition_1 + c*Income + d*Education+ e*Occupation + f*Healthcare + g*Insurance + h*Subsidies+ i*Media + j*Age + k*Urbanization+ l* Origin +m* Sex • 2nd model: Diabetes= a +b*Nutrition_2+ c*Income + d*Education+ e*Occupation + f*Healthcare + g*Insurance + h*Subsidies+ i*Media + j*Age + k*Urbanization+ l* Origin +m* Sex
Probitmodels • Diabetes_2= 1 if Diabetes>6.5O otherwise sum Diabetes, detail hba1c(mmol/l) hemoglobin a1c - field ------------------------------------------------------------- Percentiles Smallest 1% 4.1 2.7 5% 4.7 3.1 10% 4.9 3.4 Obs 9088 25% 5.2 3.5 Sum of Wgt. 9088 50% 5.5 Mean 5.593376 Largest Std. Dev. .8566354 75% 5.8 13.3 90% 6.2 14 Variance .7338243 95% 6.7 15.2 Skewness 3.638847 99% 9.7 16.1 Kurtosis 25.81249
Probitmodels • 1rst model: Diabetes_2= a + b*Nutrition_1 + c*Income + d*Education+ e*Occupation + f*Healthcare + g*Insurance + h*Subsidies+ i*Media + j*Age + k*Urbanization+ l* Origin +m* Sex • 2nd model: Diabetes_2= a + b*Nutrition_2 + c*Income + d*Education+ e*Occupation + f*Healthcare + g*Insurance + h*Subsidies+ i*Media + j*Age + k*Urbanization+ l* Origin +m* Sex
Data • China Health and Nutrition Survey(CHNS) • 1989-20092009: data for Diabetes • Merge and createdelays
1rst model: Diabetes_2= a + b*∑Nutrition_1 + c*∑Income + d*Education+ e*Occupation + f*Healthcare + g*Insurance + h*Subsidies+ i*Media + j*Age + k*Urbanization+ l* Origin +m* Sex • 2nd model: Diabetes_2= a + b*Nutrition_2 + c*∑Income + d*Education+ e*Occupation + f*Healthcare + g*Insurance + h*Subsidies+ i*Media + j*Age + k*Urbanization+ l* Origin +m* Sex
Investigation prospects • Try to ameliorate instrumentation includingcommunity variables as: « distance to fastfood » and « isthere a fastfood in the community? » • Createbinary variables for foodlikes and use this instrumentation instead • Create Nutrition variables by age (z-scores)
Challenges ahead • Use to have some arguments to taxfastfoods in China from 2006, but nothingreallyhappened. The reasons? high cost of taxation, whichwill damage interest groups (KFC, Mac Donald’s) mayderivefrom the unefficiency of China’shealth system • We suspect overweight and obesity to increasediabetesintensity. That’swhyfastfood are suspected to increasediabetesintensityindirectly, through BMI (we are going to use it as a possible instrument). • Thenitraisesnutritional and policitical recommandations: (1) space out fastfoodsfromschools to a sustainabledevelopment(2) why not taxingfastfood restaurants?(3) at least, changingtheirpolicies (whoknows in the USA and in China, buying a glas of water is more expensivethana Coke?)